Pyridylphenyl compounds for inflammation and immune-related uses

ABSTRACT

The invention relates to compounds of structural formula (I): 
                         
or a pharmaceutically acceptable salt, solvate, clathrate, or prodrug thereof, wherein Y, L, X 1 , X 2 , Z, R 3 , R 4 , and n are defined herein. These compounds are useful as immunosuppressive agents and for treating and preventing inflammatory conditions, allergic disorders, and immune disorders.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/701,170, filed Jan. 31, 2007, which claims the benefit of U.S.Provisional Application No. 60/763,782, filed Jan. 31, 2006, both ofwhich are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

This invention relates to biologically active chemical compounds, namelypyridylphenyl derivatives that may be used for immunosuppression or totreat or prevent inflammatory conditions and immune disorders.

BACKGROUND OF THE INVENTION

Inflammation is a mechanism that protects mammals from invadingpathogens. However, while transient inflammation is necessary to protecta mammal from infection, uncontrolled inflammation causes tissue damageand is the underlying cause of many illnesses. Inflammation is typicallyinitiated by binding of an antigen to T-cell antigen receptor. Antigenbinding by a T-cell initiates calcium influx into the cell via calciumion channels, such as Ca²⁺-release-activated Ca²⁺ channels (CRAC).Calcium ion influx in turn initiates a signaling cascade that leads toactivation of these cells and an inflammatory response characterized bycytokine production.

Interleukin 2 (IL-2) is a cytokine that is secreted by T cells inresponse to calcium ion influx into the cell. IL-2 modulatesimmunological effects on many cells of the immune system. For example,it is a potent T cell mitogen that is required for the T cellproliferation, promoting their progression from G1 to S phase of thecell cycle; it stimulates the growth of NK cells; and it acts as agrowth factor to B cells and stimulates antibody synthesis.

IL-2, although useful in the immune response, can cause a variety ofproblems. IL-2 damages the blood-brain barrier and the endothelium ofbrain vessels. These effects may be the underlying causes ofneuropsychiatric side effects observed under IL-2 therapy, e.g. fatigue,disorientation and depression. It also alters the electrophysiologicalbehaviour of neurons.

Due to its effects on both T and B cells, IL-2 is a major centralregulator of immune responses. It plays a role in inflammatoryreactions, tumour surveillance, and hematopoiesis. It also affects theproduction of other cytokines, inducing IL-1, TNF-α and TNF-β secretion,as well as stimulating the synthesis of IFN-γ in peripheral leukocytes.

T cells that are unable to produce IL-2 become inactive (anergic). Thisrenders them potentially inert to any antigenic stimulation they mightreceive in the future. As a result, agents which inhibit IL-2 productioncan be used for immunosupression or to treat or prevent inflammation andimmune disorders. This approach has been clinically validated withimmunosuppressive drugs such as cyclosporin, FK506, and RS61443. Despitethis proof of concept, agents that inhibit IL-2 production remain farfrom ideal. Among other problems, efficacy limitations and unwanted sideeffects (including dose-dependant nephrotoxicity and hypertension)hinder their use.

Over production of proinflammatory cytokines other than IL-2 has alsobeen implicated in many autoimmune diseases. For example, Interleukin 5(IL-5), a cytokine that increases the production of eosinophils, isincreased in asthma. Overproduction of IL-5 is associated withaccumulation of eosinophils in the asthmatic bronchial mucosa, a hallmark of allergic inflammation. Thus, patients with asthma and otherinflammatory disorders involving the accumulation of eosinophils wouldbenefit from the development of new drugs that inhibit the production ofIL-5.

Interleukin 4 (IL-4) and interleukin 13 (IL-13) have been identified asmediators of the hypercontractility of smooth muscle found ininflammatory bowel disease and asthma. Thus, patients with asthma andinflammatory bowel disease would benefit from the development of newdrugs that inhibit IL-4 and IL-13 production.

Granulocyte macrophage-colony stimulating factor (GM-CSF) is a regulatorof maturation of granulocyte and macrophage lineage population and hasbeen implicated as a key factor in inflammatory and autoimmune diseases.Anti-GM-CSF antibody blockade has been shown to ameliorate autoimmunedisease. Thus, development of new drugs that inhibit the production ofGM-CSF would be beneficial to patients with an inflammatory orautoimmune disease.

There is therefore a continuing need for new drugs which overcome one ormore of the shortcomings of drugs currently used for immunosuppressionor in the treatment or prevention of inflammatory disorders, allergicdisorders and autoimmune disorders. Desirable properties of new drugsinclude efficacy against diseases or disorders that are currentlyuntreatable or poorly treatable, new mechanism of action, oralbioavailability and/or reduced side effects.

SUMMARY OF THE INVENTION

This invention meets the above-mentioned needs by providing certainpyridylphenyl derivatives that inhibit the activity of CRAC ion channelsand inhibit the production of IL-2, IL-4, IL-5, IL-13, GM-CSF, TNF-α,and IFNγ. These compounds are particularly useful for immunosuppressionand/or to treat or prevent inflammatory conditions and immune disorders.

The invention relates to compounds of formula (I):

-   -   or a pharmaceutically acceptable salt, solvate, clathrate, or        prodrug thereof, wherein:    -   Y is a monocyclic optionally substituted aryl or a monocyclic        optionally substituted heteroaryl;    -   L is a linker selected from the group consisting of —NRCR₂—,        —CR₂NR—, —C(O)—, —NR—C(O)—, —C(O)—NR—, —OC(O)—, —C(O)O—, —C(S)—,        —NR—C(S)—, —C(S)—NR—;    -   one of X₁ or X₂ is CH or CZ and the other is N;    -   each Z is independently selected from the group consisting of a        lower alkyl, a lower haloalkyl, a halo, a lower alkoxy, a lower        alkyl sulfanyl, —S(O)_(p)-alkyl, —C(O)NRR, —(CH₂)_(k)NRR,        —(CH₂)_(k)OR, —(CH₂)_(k)SR, cyano, nitro, or lower haloalkoxy;    -   R, for each occurrence is independently selected from —H or an        alkyl;    -   R₃ is H, an alkyl, a haloalkyl, a halo, a haloalkoxy, —OR₅,        —SR₅, or —NR₆R₇;    -   R₄ is a halo, a haloalkyl, cyano, nitro, —C(O)R₅, —C(O)OR₅,        —C(O)SR₅, —C(O)NR₉R₁₀, —C(S)R₅, —C(S)OR₅, —C(S)SR₅, —C(S)NR₆R₇,        —C(NR₈)R₅, —C(NR₈)OR₅, —C(NR₈)SR₅, —C(NR₈)NR₈R₇, —S(O)_(p)R₅,        —S(O)_(p)NR₅, —S(O)_(p)OR₅, —P(O)(OR₅)₂, —OP(O)(OR₅)₂,        —P(O)(R₅)₂, an optionally substituted heterocyclyl, or an        optionally substituted heteroaryl;    -   R₅, for each occurrence, is independently, H, an optionally        substituted alkyl, an optionally substituted alkenyl, an        optionally substituted alkynyl, an optionally substituted        cycloalkyl, an optionally substituted cycloalkenyl, an        optionally substituted heterocyclyl, an optionally substituted        aryl, an optionally substituted heteroaryl, an optionally        substituted aralkyl, or an optionally substituted heteraralkyl;    -   R₆ and R₇, for each occurrence are, independently, H, an        optionally substituted alkyl, an optionally substituted alkenyl,        an optionally substituted alkynyl, an optionally substituted        cycloalkyl, an optionally substituted cycloalkenyl, an        optionally substituted heterocyclyl, an optionally substituted        aryl, an optionally substituted heteroaryl, an optionally        substituted aralkyl, or an optionally substituted heteraralkyl;        or R₆ and R₇ taken together with the nitrogen to which they are        attached are an optionally substituted heterocyclyl or        optionally substituted heteroaryl;    -   R₈, for each occurrence, is independently —H, a halo, an alkyl,        —OR₅, —NR₆R₇, —C(O)R₅, —C(O)OR₅, or —C(O)NR₆R₇;    -   R₉ and R₁₀, for each occurrence are, independently, H, an        optionally substituted alkyl, an optionally substituted alkenyl,        an optionally substituted alkynyl, an optionally substituted 5-        to 14-membered cycloalkyl, an optionally substituted        cycloalkenyl, an optionally substituted heterocyclyl, an        optionally substituted aryl, an optionally substituted aralkyl,        an optionally substituted heteraralkyl, or an optionally        substituted heteroaryl selected from the group consisting of an        optionally substituted pyridinyl, an optionally substituted        thienyl, an optionally substituted pyrrolyl, an optionally        substituted oxazolyl, an optionally substituted imidazolyl, an        optionally substituted indolizinyl, an optionally substituted        isoxazolyl, an optionally substituted pyrazolyl, an optionally        substituted isothiazolyl, an optionally substituted pyridazinyl,        an optionally substituted pyrimidinyl, an optionally substituted        pyrazinyl, an optionally substituted triazinyl, an optionally        substituted triazolyl, an optionally substituted pyridinyl, an        optionally substituted thiadiazolyl, an optionally substituted        pyrazinyl, an optionally substituted quinolinyl, an optionally        substituted isoquinolinyl, an optionally substituted indazolyl,        an optionally substituted benzoxazolyl, an optionally        substituted benzofuryl, an optionally substituted        benzothiazolyl, an optionally substituted indolizinyl, an        optionally substituted imidazopyridinyl, an optionally        substituted tetrazolyl, an optionally substituted        benzimidazolyl, an optionally substituted benzoxazolyl, an        optionally substituted benzothiazolyl, an optionally substituted        benzothiadiazolyl, an optionally substituted benzoxadiazolyl, an        optionally substituted indolyl, an optionally substituted        tetrahydroindolyl, an optionally substituted azaindolyl, an        optionally substituted imidazopyridyl, an optionally substituted        qunizaolinyl, an optionally substituted purinyl, an optionally        substituted pyrrolo[2,3]pyrimidyl, an optionally substituted        pyrazolo[3,4]pyrimidyl or an optionally substituted        benzo(b)thienyl; or R₉ and R₁₀ taken together with the nitrogen        to which they are attached are an optionally substituted        heterocyclyl or optionally substituted heteroaryl;    -   q, for each occurrence, is independently, an integer from 1 to        3;    -   k is for each occurrence, is independently, an integer from 1 to        4;    -   n is zero, 1 or 2; and    -   p, for each occurrence, is independently 1 or 2.

A compound of the invention or a pharmaceutically acceptable salt,solvate, clathrate, or prodrug thereof is particularly useful inhibitingimmune cell (e.g., T-cells and/or B-cells) activation (e.g., activationin response to an antigen). In particular, a compound of the inventionor a pharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof can inhibit the production of certain cytokines that regulateimmune cell activation. For example, a compound of the invention or apharmaceutically acceptable salt, solvate, clathrate, or prodrug thereofcan inhibit the production of IL-2, IL-4, IL-5, IL-13, GM-CSF, TNF-α,INF-γ or combinations thereof. Moreover, a compound of the invention ora pharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof can modulate the activity of one or more ion channel involved inactivation of immune cells, such as CRAC ion channels.

A compound of the invention or a pharmaceutically acceptable salt,solvate, clathrate, or prodrug thereof is particularly useful forimmunosuppression or for treating or preventing inflammatory conditions,allergic disorders, and immune disorders.

The invention also encompasses pharmaceutical compositions comprising acompound of the invention or a pharmaceutically acceptable salt,solvate, clathrate, or prodrug thereof; and a pharmaceuticallyacceptable carrier or vehicle. These compositions may further compriseadditional agents. These compositions are useful for immunosuppressionand treating or preventing inflammatory conditions, allergic disordersand immune disorders.

The invention further encompasses methods for treating or preventinginflammatory conditions, allergic disorders, and immune disorders,comprising administering to a subject in need thereof an effectiveamount of a compound of the invention or a pharmaceutically acceptablesalt, solvate, clathrate, or prodrug thereof, or a pharmaceuticalcomposition comprising a compound of the invention or a pharmaceuticallyacceptable salt, solvate, clathrate, or prodrug thereof. These methodsmay also comprise administering to the subject an additional agentseparately or in a combination composition with the compound of theinvention or a pharmaceutically acceptable salt, solvate, clathrate, orprodrug thereof.

The invention further encompasses methods for suppressing the immunesystem of a subject, comprising administering to a subject in needthereof an effective amount of a compound of the invention or apharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof, or a pharmaceutical composition comprising a compound of theinvention or a pharmaceutically acceptable salt, solvate, clathrate, orprodrug thereof. These methods may also comprise administering to thesubject an additional agent separately or in a combination compositionwith the compound of the invention or a pharmaceutically acceptablesalt, solvate, clathrate, or prodrug thereof.

The invention further encompasses methods for inhibiting immune cellactivation, including inhibiting proliferation of T cells and/or Bcells, in vivo or in vitro comprising administering to the cell aneffective amount of a compound of the invention or a pharmaceuticallyacceptable salt, solvate, clathrate, or prodrug thereof or apharmaceutical composition comprising a compound of the invention or apharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof.

The invention further encompasses methods for inhibiting cytokineproduction in a cell, (e.g., IL-2, IL-4, IL-5, IL-13, GM-CSF, TNF-α,and/or INF-γ production) in vivo or in vitro comprising administering toa cell an effective amount of a compound of the invention or apharmaceutically acceptable salt, solvate, clathrate, or prodrug thereofor a pharmaceutical composition comprising a compound of the inventionor a pharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof.

The invention further encompasses methods for modulating ion channelactivity (e.g., CRAC) in vivo or in vitro comprising administering aneffective amount of a compound of the invention or a pharmaceuticallyacceptable salt, solvate, clathrate, or prodrug thereof or apharmaceutical composition comprising a compound of the invention or apharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof.

All of the methods of this invention may be practice with a compound ofthe invention alone, or in combination with other agents, such as otherimmunosuppressive agents, anti-inflammatory agents, agents for thetreatment of allergic disorders or agents for the treatment of immunedisorders.

DETAILED DESCRIPTION OF THE INVENTION Definitions

Unless otherwise specified, the below terms used herein are defined asfollows:

As used herein, the term an “aromatic ring” or “aryl” means a monocyclicor polycyclic-aromatic ring or ring radical comprising carbon andhydrogen atoms. Examples of suitable aryl groups include, but are notlimited to, phenyl, tolyl, anthacenyl, fluorenyl, indenyl, azulenyl, andnaphthyl, as well as benzo-fused carbocyclic moieties such as5,6,7,8-tetrahydronaphthyl. An aryl group can be unsubstituted orsubstituted with one or more substituents (including without limitationalkyl (preferably, lower alkyl or alkyl substituted with one or morehalo), hydroxy, alkoxy (preferably, lower alkoxy), alkylthio, cyano,halo, amino, and nitro. In certain embodiments, the aryl group is amonocyclic ring, wherein the ring comprises 6 carbon atoms.

As used herein, the term “alkyl” means a saturated straight chain orbranched non-cyclic hydrocarbon typically having from 1 to 10 carbonatoms. Representative saturated straight chain alkyls include methyl,ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyland n-decyl; while saturated branched alkyls include isopropyl,sec-butyl, isobutyl, tert-butyl, isopentyl, 2-methylbutyl,3-methylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl,2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl,2,3-dimethylbutyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl,2,3-dimethylhexyl, 2,4-dimethylhexyl, 2,5-dimethylhexyl,2,2-dimethylpentyl, 2,2-dimethylhexyl, 3,3-dimethylpentyl,3,3-dimethylhexyl, 4,4-dimethylhexyl, 2-ethylpentyl, 3-ethylpentyl,2-ethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 2-methyl-2-ethylpentyl,2-methyl-3-ethylpentyl, 2-methyl-4-ethylpentyl, 2-methyl-2-ethylhexyl,2-methyl-3-ethylhexyl, 2-methyl-4-ethylhexyl, 2,2-diethylpentyl,3,3-diethylhexyl, 2,2-diethylhexyl, 3,3-diethylhexyl and the like. Alkylgroups included in compounds of this invention may be optionallysubstituted with one or more substituents, such as amino, alkylamino,alkoxy, alkylthio, oxo, halo, acyl, nitro, hydroxyl, cyano, aryl,alkylaryl, aryloxy, arylthio, arylamino, carbocyclyl, carbocyclyloxy,carbocyclylthio, carbocyclylamino, heterocyclyl, heterocyclyloxy,heterocyclylamino, heterocyclylthio, and the like. In addition, anycarbon in the alkyl segment may be substituted with oxygen (═O), sulfur(═S), or nitrogen (═NR²³, wherein R²³ is —H, an alkyl, acetyl, oraralkyl). Lower alkyls are typically preferred for the compounds of thisinvention.

The term alkylene refers to an alkyl group that has two points ofattachment to two moieties (e.g., {—CH₂—}, —{CH₂CH₂—},

etc., wherein the brackets indicate the points of attachment). Alkylenegroups may be substituted or unsubstituted.

An aralkyl group refers to an aryl group that is attached to anothermoiety via an alkylene linker. Aralkyl groups can be substituted orunsubstituted.

The term “alkoxy,” as used herein, refers to an alkyl group which islinked to another moiety though an oxygen atom. Alkoxy groups can besubstituted or unsubstituted.

The term “alkoxyalkoxy,” as used herein, refers to an alkoxy group inwhich the alkyl portion is substituted with another alkoxy group.

The term “alkyl sulfanyl,” as used herein, refers to an alkyl groupwhich is linked to another moiety though a divalent sulfur atom. Alkylsulfanyl groups can be substituted or unsubstituted.

The term “alkylamino,” as used herein, refers to an amino group in whichone hydrogen atom attached to the nitrogen has been replaced by an alkylgroup. The term “dialkylamino,” as used herein, refers to an amino groupin which two hydrogen atoms attached to the nitrogen have been replacedby alkyl groups, in which the alkyl groups can be the same or different.Alkylamino groups and dialkylamino groups can be substituted orunsubstituted.

As used herein, the term “alkenyl” means a straight chain or branched,hydrocarbon radical typically having from 2 to 10 carbon atoms andhaving at least one carbon-carbon double bond. Representative straightchain and branched alkenyls include vinyl, allyl, 1-butenyl, 2-butenyl,isobutylenyl, 1-pentenyl, 2-pentenyl, 3-methyl-1-butenyl,1-methyl-2-butenyl, 2,3-dimethyl-2-butenyl, 1-hexenyl, 2-hexenyl,3-hexenyl, 1-heptenyl, 2-heptenyl, 3-heptenyl, 1-octenyl, 2-octenyl,3-octenyl, 1-nonenyl, 2-nonenyl, 3-nonenyl, 1-decenyl, 2-decenyl,3-decenyl and the like. Alkenyl groups can be substituted orunsubstituted.

As used herein, the term “alkynyl” means a straight chain or branched,hydrocarbon radical typically having from 2 to 10 carbon atoms andhaving at lease one carbon-carbon triple bond. Representative straightchain and branched alkynyls include acetylenyl, propynyl, 1-butynyl,2-butynyl, 1-pentynyl, 2-pentynyl, 3-methyl-1-butynyl,4-pentynyl,-1-hexynyl, 2-hexynyl, 5-hexynyl, 1-heptynyl, 2-heptynyl,6-heptynyl, 1-octynyl, 2-octynyl, 7-octynyl, 1-nonynyl, 2-nonynyl,8-nonynyl, 1-decynyl, 2-decynyl, 9-decynyl and the like. Alkynyl groupscan be substituted or unsubstituted.

As used herein, the term “cycloalkyl” means a saturated, mono- orpolycyclic alkyl radical typically having from 3 to 10 carbon atoms.Representative cycloalkyls include cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, adamantly,decahydronaphthyl, octahydropentalene, bicycle[1.1.1]pentanyl, and thelike. Cycloalkyl groups can be substituted or unsubstituted.

As used herein, the term “cycloalkenyl” means a cyclic non-aromaticalkenyl radical having at least one carbon-carbon double bond in thecyclic system and typically having from 5 to 10 carbon atoms.Representative cycloalkenyls include cyclopentenyl, cyclopentadienyl,cyclohexenyl, cyclohexadienyl, cycloheptenyl, cycloheptadienyl,cycloheptatrienyl, cyclooctenyl, cyclooctadienyl, cyclooctatrienyl,cyclooctatetraenyl, cyclononenyl, cyclononadienyl, cyclodecenyl,cyclodecadienyl and the like. Cycloalkenyl groups can be substituted orunsubstituted.

As used herein, the term “heterocycle” or “heterocyclyl” means amonocyclic or polycyclic heterocyclic ring (typically having 3- to14-members) which is either a saturated ring or an unsaturatednon-aromatic ring. A 3-membered heterocycle can contain up to 3heteroatoms, and a 4- to 14-membered heterocycle can contain from 1 toabout 8 heteroatoms. Each heteroatom is independently selected fromnitrogen, which can be quaternized; oxygen; and sulfur, includingsulfoxide and sulfone. The heterocycle may be attached via anyheteroatom or carbon atom. Representative heterocycles includemorpholinyl, thiomorpholinyl, pyrrolidinonyl, pyrrolidinyl, piperidinyl,piperazinyl, hydantoinyl, valerolactamyl, oxiranyl, oxetanyl,tetrahydrofuranyl, tetrahydropyranyl, tetrahydropyrindinyl,tetrahydropyrimidinyl, tetrahydrothiophenyl, tetrahydrothiopyranyl, andthe like. A heteroatom may be substituted with a protecting group knownto those of ordinary skill in the art, for example, the hydrogen on anitrogen may be substituted with a tert-butoxycarbonyl group.Furthermore, the heterocyclyl may be optionally substituted with one ormore substituents (including without limitation a halogen atom, an alkylradical, or aryl radical). Only stable isomers of such substitutedheterocyclic groups are contemplated in this definition. Heterocyclylgroups can be substituted or unsubstituted.

As used herein, the term “heteroaromatic” or “heteroaryl” means amonocyclic or polycyclic heteroaromatic ring (or radical thereof)comprising carbon atom ring members and one or more heteroatom ringmembers (such as, for example, oxygen, sulfur or nitrogen). Typically,the heteroaromatic ring has from 5 to about 14 ring members in which atleast 1 ring member is a heteroatom selected from oxygen, sulfur andnitrogen. In another embodiment, the heteroaromatic ring is a 5 or 6membered ring and may contain from 1 to about 4 heteroatoms. In anotherembodiment, the heteroaromatic ring system has a 7 to 14 ring membersand may contain from 1 to about 7 heteroatoms. Representativeheteroaryls include pyridyl, furyl, thienyl, pyrrolyl, oxazolyl,imidazolyl, indolizinyl, thiazolyl, isoxazolyl, pyrazolyl, isothiazolyl,pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, triazolyl, pyridinyl,thiadiazolyl, pyrazinyl, quinolyl, isoquinolyl, indazolyl, benzoxazolyl,benzofuryl, benzothiazolyl, indolizinyl, imidazopyridinyl, isothiazolyl,tetrazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl,benzothiadiazolyl, benzoxadiazolyl, indolyl, tetrahydroindolyl,azaindolyl, imidazopyridyl, qunizaolinyl, purinyl,pyrrolo[2,3]pyrimidyl, pyrazolo[3,4]pyrimidyl or benzo(b)thienyl and thelike. These heteroaryl groups may be optionally substituted with one ormore substituents

A heteroaralkyl group refers to a heteroaryl group that is attached toanother moiety via an alkylene linker. Heteroaralkyl groups can besubstituted or unsubstituted.

As used herein, the term “halogen” or “halo” means —F, —Cl, —Br or —I.

As used herein, the term “haloalkyl” means an alkyl group in which oneor more —H is replaced with a halo group. Examples of haloalkyl groupsinclude —CF₃, —CHF₂, —CCl₃, —CH₂CH₂Br, —CH₂CH(CH₂CH₂Br)CH₃, —CHICH₃, andthe like.

As used herein, the term “haloalkoxy” means an alkoxy group in which oneor more —H is replaced with a halo group. Examples of haloalkoxy groupsinclude —OCF₃ and —OCHF₂.

The terms “bioisostere” and “bioisosteric replacement” have the samemeanings as those generally recognized in the art. Bioisosteres areatoms, ions, or molecules in which the peripheral layers of electronscan be considered substantially identical. The term bioisostere isusually used to mean a portion of an overall molecule, as opposed to theentire molecule itself. Bioisosteric replacement involves using onebioisostere to replace another with the expectation of maintaining orslightly modifying the biological activity of the first bioisostere. Thebioisosteres in this case are thus atoms or groups of atoms havingsimilar size, shape and electron density. Preferred bioisosteres ofesters, amides or carboxylic acids are compounds containing two sitesfor hydrogen bond acceptance. In one embodiment, the ester, amide orcarboxylic acid bioisostere is a 5-membered monocyclic heteroaryl ring,such as an optionally substituted 1H-imidazolyl, an optionallysubstituted oxazolyl, 1H-tetrazolyl, [1,2,4]triazolyl, or an optionallysubstituted [1,2,4]oxadiazolyl.

As used herein, the terms “subject”, “patient” and “animal”, are usedinterchangeably and include, but are not limited to, a cow, monkey,horse, sheep, pig, chicken, turkey, quail, cat, dog, mouse, rat, rabbit,guinea pig and human. The preferred subject, patient or animal is ahuman.

As used herein, the term “lower” refers to a group having up to fourcarbon atoms. For example, a “lower alkyl” refers to an alkyl radicalhaving from 1 to 4 carbon atoms, and a “lower alkenyl” or “loweralkynyl” refers to an alkenyl or alkynyl radical having from 2 to 4carbon atoms, respectively. A lower alkoxy or a lower alkyl sulfanylrefers to an alkoxy or a alkyl sulfanyl having from 1 to 4 carbon atoms.Lower substituents are typically preferred.

Where a particular substituent, such as an alkyl substituent, occursmultiple times in a given structure or moeity, the identity of thesubstitutent is independent in each case and may be the same as ordifferent from other occurrences of that substituent in the structure ormoiety. Furthermore, individual substituents in the specific embodimentsand exemplary compounds of this invention are preferred in combinationwith other such substituents in the compounds of this invention, even ifsuch individual substituents are not expressly noted as being preferredor not expressly shown in combination with other substituents.

The compounds of the invention are defined herein by their chemicalstructures and/or chemical names. Where a compound is referred to byboth a chemical structure and a chemical name, and the chemicalstructure and chemical name conflict, the chemical structure isdeterminative of the compound's identity.

Suitable substituents for an alkyl, alkoxy, alkyl sulfanyl, alkylamino,dialkylamino, alkylene, alkenyl, alkynyl, cycloalkyl, cycloalkenyl,heterocyclyl, aryl, aralkyl, heteroaryl, and heteroarylalkyl groupsinclude any substituent which will form a stable compound of theinvention. Examples of substituents for an alkyl, alkoxy, alkylsulfanyl,alkylamino, dialkylamino, alkylene, alkenyl, alkynyl, cycloalkyl,cycloalkenyl, heterocyclyl, aryl, aralkyl, heteroaryl, andheteroarylalkyl include an alkyl, alkoxy, alkyl sulfanyl, alkylamino,dialkylamino, an alkenyl, an alkynyl, an cycloalkyl, an cycloalkenyl, anheterocyclyl, an aryl, an heteroaryl, an aralkyl, an heteraralkyl, ahaloalkyl, —C(O)NR₁₃R₁₄, —NR₁₅C(O)R₁₆, halo, —OR₁₅, cyano, nitro,haloalkoxy, —C(O)R₁₅, —NR₁₃R₁₄, —SR₁₅, —C(O)OR₁₅, —OC(O)R₁₅,—NR₁₅C(O)NR₁₃R₁₄, —OC(O)NR₁₃R₁₄, —NR₁₅C(O)OR₁₆, —S(O)_(p)R₁₅, or—S(O)_(p)NR₁₃R₁₄, wherein R₁₃ and R₁₄, for each occurrence are,independently, H, an optionally substituted alkyl, an optionallysubstituted alkenyl, an optionally substituted alkynyl, an optionallysubstituted cycloalkyl, an optionally substituted cycloalkenyl, anoptionally substituted heterocyclyl, an optionally substituted aryl, anoptionally substituted heteroaryl, an optionally substituted aralkyl, oran optionally substituted heteraralkyl; or R₁₃ and R₁₄ taken togetherwith the nitrogen to which they are attached is optionally substitutedheterocyclyl or optionally substituted heteroaryl; and R₁₅ and R₁₆ foreach occurrence are, independently, H, an optionally substituted alkyl,an optionally substituted alkenyl, an optionally substituted alkynyl, anoptionally substituted cycloalkyl, an optionally substitutedcycloalkenyl, an optionally substituted heterocyclyl, an optionallysubstituted aryl, an optionally substituted heteroaryl, an optionallysubstituted aralkyl, or an optionally substituted heteraralkyl;

In addition, alkyl, cycloalkyl, alkylene, a heterocyclyl, and anysaturated portion of a alkenyl, cycloalkenyl, alkynyl, aralkyl, andheteroaralkyl groups, may also be substituted with ═O, ═S, ═N—R₁₅.

When a heterocyclyl, heteroaryl, or heteroaralkyl group contains anitrogen atom, it may be substituted or unsubstituted. When a nitrogenatom in the aromatic ring of a heteroaryl group has a substituent thenitrogen may be a quaternary nitrogen.

Choices and combinations of substituents and variables envisioned bythis invention are only those that result in the formation of stablecompounds. The term “stable”, as used herein, refers to compounds whichpossess stability sufficient to allow manufacture and which maintainsthe integrity of the compound for a sufficient period of time to beuseful for the purposes detailed herein (e.g., therapeutic orprophylactic administration to a subject). Typically, such compounds arestable at a temperature of 40° C. or less, in the absence of excessivemoisture, for at least one week. Such choices and combinations will beapparent to those of ordinary skill in the art and may be determinedwithout undue experimentation.

Unless indicated otherwise, the compounds of the invention containingreactive functional groups (such as, without limitation, carboxy,hydroxy, and amino moieties) also include protected derivatives thereof.“Protected derivatives” are those compounds in which a reactive site orsites are blocked with one or more protecting groups. Suitableprotecting groups for carboxy moieties include benzyl, tert-butyl, andthe like. Suitable protecting groups for amino and amido groups includeacetyl, tert-butoxycarbonyl, benzyloxycarbonyl, and the like. Suitableprotecting groups for hydroxy include benzyl and the like. Othersuitable protecting groups are well known to those of ordinary skill inthe art and include those found in T. W. Greene, Protecting Groups inOrganic Synthesis, John Wiley & Sons, Inc. 1981, the entire teachings ofwhich are incorporated herein by reference.

As used herein, the term “compound(s) of this invention” and similarterms refers to a compound of any one of formulas (I) through (II), orTable 1, or a pharmaceutically acceptable salt, solvate, clathrate, orprodrug thereof and also include protected derivatives thereof.

As used herein and unless otherwise indicated, the term “prodrug” meansa derivative of a compound that can hydrolyze, oxidize, or otherwisereact under biological conditions (in vitro or in vivo) to provide acompound of this invention. Prodrugs may only become active upon suchreaction under biological conditions, but they may have activity intheir unreacted forms. Examples of prodrugs contemplated in thisinvention include, but are not limited to, analogs or derivatives ofcompounds of any one of formulas (I) through (II), or Table 1 thatcomprise biohydrolyzable moieties such as biohydrolyzable amides,biohydrolyzable esters, biohydrolyzable carbamates, biohydrolyzablecarbonates, biohydrolyzable ureides, and biohydrolyzable phosphateanalogues. Other examples of prodrugs include derivatives of compoundsof any one of formulas (I) through (II), or of Table 1 that comprise—NO, —NO₂, —ONO, or —ONO₂ moieties. Prodrugs can typically be preparedusing well-known methods, such as those described by 1 BURGER'SMEDICINAL CHEMISTRY AND DRUG DISCOVERY (1995) 172-178, 949-982 (ManfredE. Wolff ed. 5^(th) ed), the entire teachings of which are incorporatedherein by reference.

As used herein and unless otherwise indicated, the terms“biohydrolyzable amide”, “biohydrolyzable ester”, “biohydrolyzablecarbamate”, “biohydrolyzable carbonate”, “biohydrolyzable ureide” and“biohydrolyzable phosphate analogue” mean an amide, ester, carbamate,carbonate, ureide, or phosphate analogue, respectively, that either: 1)does not destroy the biological activity of the compound and confersupon that compound advantageous properties in vivo, such as uptake,duration of action, or onset of action; or 2) is itself biologicallyinactive but is converted in vivo to a biologically active compound.Examples of biohydrolyzable amides include, but are not limited to,lower alkyl amides, α-amino acid amides, alkoxyacyl amides, andalkylaminoalkylcarbonyl amides. Examples of biohydrolyzable estersinclude, but are not limited to, lower alkyl esters, alkoxyacyloxyesters, alkyl acylamino alkyl esters, and choline esters. Examples ofbiohydrolyzable carbamates include, but are not limited to, loweralkylamines, substituted ethylenediamines, aminoacids,hydroxyalkylamines, heterocyclic and heteroaromatic amines, andpolyether amines.

As used herein, the term “pharmaceutically acceptable salt,” is a saltformed from an acid and a basic group of one of the compounds of any oneof formulas (I) through (II) or of Table 1. Illustrative salts include,but are not limited, to sulfate, citrate, acetate, oxalate, chloride,bromide, iodide, nitrate, bisulfate, phosphate, acid phosphate,isonicotinate, lactate, salicylate, acid citrate, tartrate, oleate,tannate, pantothenate, bitartrate, ascorbate, succinate, maleate,gentisinate, fumarate, gluconate, glucaronate, saccharate, formate,benzoate, glutamate, methanesulfonate, ethanesulfonate,benzenesulfonate, p-toluenesulfonate, and pamoate (i.e.,1,1′-methylene-bis-(2-hydroxy-3-naphthoate)) salts. The term“pharmaceutically acceptable salt” also refers to a salt prepared from acompound of any one of formulas (I) through (II) or Table 1 having anacidic functional group, such as a carboxylic acid functional group, anda pharmaceutically acceptable inorganic or organic base. Suitable basesinclude, but are not limited to, hydroxides of alkali metals such assodium, potassium, and lithium; hydroxides of alkaline earth metal suchas calcium and magnesium; hydroxides of other metals, such as aluminumand zinc; ammonia, and organic amines, such as unsubstituted orhydroxy-substituted mono-, di-, or trialkylamines; dicyclohexylamine;tributyl amine; pyridine; N-methyl, N-ethylamine; diethylamine;triethylamine; mono-, bis-, or tris-(2-hydroxy-lower alkyl amines), suchas mono-, bis-, or tris-(2-hydroxyethyl)-amine,2-hydroxy-tert-butylamine, or tris-(hydroxymethyl)methylamine,N,N,-di-lower alkyl-N-(hydroxy lower alkyl)-amines, such asN,N-dimethyl-N-(2-hydroxyethyl)-amine, or tri-(2-hydroxyethyl)amine;N-methyl-D-glucamine; and amino acids such as arginine, lysine, and thelike. The term “pharmaceutically acceptable salt” also refers to a saltprepared from a compound of any one of formulas (I) through (II) orTable 1 having a basic functional group, such as an amino functionalgroup, and a pharmaceutically acceptable inorganic or organic acid.Suitable acids include, but are not limited to, hydrogen sulfate, citricacid, acetic acid, oxalic acid, hydrochloric acid, hydrogen bromide,hydrogen iodide, nitric acid, phosphoric acid, isonicotinic acid, lacticacid, salicylic acid, tartaric acid, ascorbic acid, succinic acid,maleic acid, besylic acid, fumaric acid, gluconic acid, glucaronic acid,saccharic acid, formic acid, benzoic acid, glutamic acid,methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, andp-toluenesulfonic acid.

As used herein, the term “pharmaceutically acceptable solvate,” is asolvate formed from the association of one or more solvent molecules toone or more molecules of a compound of any one of formulas (I) through(II) or Table 1. The term solvate includes hydrates (e.g., hemi-hydrate,mono-hydrate, dihydrate, trihydrate, tetrahydrate, and the like).

As used herein, the term “clathrate” means a compound of the presentinvention or a salt thereof in the form of a crystal lattice thatcontains spaces (e.g., channels) that have a guest molecule (e.g., asolvent or water) trapped within.

As used herein, the term “asthma” means a pulmonary disease, disorder orcondition characterized by reversible airway obstruction, airwayinflammation, and increased airway responsiveness to a variety ofstimuli.

“Immunosuppression” refers to impairment of any component of the immunesystem resulting in decreased immune function. This impairment may bemeasured by any conventional means including whole blood assays oflymphocyte function, detection of lymphocyte proliferation andassessment of the expression of T cell surface antigens. The antisheepred blood cell (SRBC) primary (IgM) antibody response assay (usuallyreferred to as the plaque assay) is one specific method. This and othermethods are described in Luster, M. I., Portier, C., Pait, D. G., White,K. L., Jr., Gennings, C., Munson, A. E., and Rosenthal, G. J. (1992).“Risk Assessment in Immunotoxicology I: Sensitivity and Predictabilityof Immune Tests.” Fundam. Appl. Toxicol., 18, 200-210. Measuring theimmune response to a T-cell dependent immunogen is another particularlyuseful assay (Dean, J. H., House, R. V., and Luster, M. I. (2001).“Immunotoxicology: Effects of, and Responses to, Drugs and Chemicals.”In Principles and Methods of Toxicology: Fourth Edition (A. W. Hayes,Ed.), pp. 1415-1450, Taylor & Francis, Philadelphia, Pa.).

The compounds of this invention can be used to treat subjects withimmune disorders. As used herein, the term “immune disorder” and liketerms means a disease, disorder or condition caused by the immune systemof an animal, including autoimmune disorders. Immune disorders includethose diseases, disorders or conditions that have an immune componentand those that are substantially or entirely immune system-mediated.Autoimmune disorders are those wherein the animal's own immune systemmistakenly attacks itself, thereby targeting the cells, tissues, and/ororgans of the animal's own body. For example, the autoimmune reaction isdirected against the nervous system in multiple sclerosis and the gut inCrohn's disease. In other autoimmune disorders such as systemic lupuserythematosus (lupus), affected tissues and organs may vary amongindividuals with the same disease. One person with lupus may haveaffected skin and joints whereas another may have affected skin, kidney,and lungs. Ultimately, damage to certain tissues by the immune systemmay be permanent, as with destruction of insulin-producing cells of thepancreas in Type 1 diabetes mellitus. Specific autoimmune disorders thatmay be ameliorated using the compounds and methods of this inventioninclude without limitation, autoimmune disorders of the nervous system(e.g., multiple sclerosis, myasthenia gravis, autoimmune neuropathiessuch as Guillain-Barré, and autoimmune uveitis), autoimmune disorders ofthe blood (e.g., autoimmune hemolytic anemia, pernicious anemia, andautoimmune thrombocytopenia), autoimmune disorders of the blood vessels(e.g., temporal arteritis, anti-phospholipid syndrome, vasculitides suchas Wegener's granulomatosis, and Behcet's disease), autoimmune disordersof the skin (e.g., psoriasis, dermatitis herpetiformis, pemphigusvulgaris, and vitiligo), autoimmune disorders of the gastrointestinalsystem (e.g., Crohn's disease, ulcerative colitis, primary biliarycirrhosis, and autoimmune hepatitis), autoimmune disorders of theendocrine glands (e.g., Type 1 or immune-mediated diabetes mellitus,Grave's disease. Hashimoto's thyroiditis, autoimmune oophoritis andorchitis, and autoimmune disorder of the adrenal gland); and autoimmunedisorders of multiple organs (including connective tissue andmusculoskeletal system diseases) (e.g., rheumatoid arthritis, systemiclupus erythematosus, scleroderma, polymyositis, dermatomyositis,spondyloarthropathies such as ankylosing spondylitis, and Sjogren'ssyndrome). In addition, other immune system mediated diseases, such asgraft-versus-host disease and allergic disorders, are also included inthe definition of immune disorders herein. Because a number of immunedisorders are caused by inflammation, there is some overlap betweendisorders that are considered immune disorders and inflammatorydisorders. For the purpose of this invention, in the case of such anoverlapping disorder, it may be considered either an immune disorder oran inflammatory disorder. “Treatment of an immune disorder” hereinrefers to administering a compound or a composition of the invention toa subject, who has an immune disorder, a symptom of such a disease or apredisposition towards such a disease, with the purpose to cure,relieve, alter, affect, or prevent the autoimmune disorder, the symptomof it, or the predisposition towards it.

As used herein, the term “allergic disorder” means a disease, conditionor disorder associated with an allergic response against normallyinnocuous substances. These substances may be found in the environment(such as indoor air pollutants and aeroallergens) or they may benon-environmental (such as those causing dermatological or foodallergies). Allergens can enter the body through a number of routes,including by inhalation, ingestion, contact with the skin or injection(including by insect sting). Many allergic disorders are linked toatopy, a predisposition to generate the allergic antibody IgE. BecauseIgE is able to sensitize mast cells anywhere in the body, atopicindividuals often express disease in more than one organ. For thepurpose of this invention, allergic disorders include anyhypersensitivity that occurs upon re-exposure to the sensitizingallergen, which in turn causes the release of inflammatory mediators.Allergic disorders include without limitation, allergic rhinitis (e.g.,hay fever), sinusitis, rhinosinusitis, chronic or recurrent otitismedia, drug reactions, insect sting reactions, latex reactions,conjunctivitis, urticaria, anaphylaxis and anaphylactoid reactions,atopic dermatitis, asthma and food allergies.

The compounds of this invention can be used to prevent or to treatsubjects with inflammatory disorders. As used herein, an “inflammatorydisorder” means a disease, disorder or condition characterized byinflammation of body tissue or having an inflammatory component. Theseinclude local inflammatory responses and systemic inflammation. Examplesof such inflammatory disorders include: transplant rejection, includingskin graft rejection; chronic inflammatory disorders of the joints,including arthritis, rheumatoid arthritis, osteoarthritis and bonediseases associated with increased bone resorption; inflammatory boweldiseases such as ileitis, ulcerative colitis, Barrett's syndrome, andCrohn's disease; inflammatory lung disorders such as asthma, adultrespiratory distress syndrome, and chronic obstructive airway disease;inflammatory disorders of the eye including corneal dystrophy, trachoma,onchocerciasis, uveitis, sympathetic ophthalmitis and endophthalmitis;chronic inflammatory disorders of the gums, including gingivitis andperiodontitis; tuberculosis; leprosy; inflammatory diseases of thekidney including uremic complications, glomerulonephritis and nephrosis;inflammatory disorders of the skin including sclerodermatitis, psoriasisand eczema; inflammatory diseases of the central nervous system,including chronic demyelinating diseases of the nervous system, multiplesclerosis, AIDS-related neurodegeneration and Alzheimer's disease,infectious meningitis, encephalomyelitis, Parkinson's disease,Huntington's disease, amyotrophic lateral sclerosis and viral orautoimmune encephalitis; autoimmune disorders, immune-complexvasculitis, systemic lupus and erythematodes; systemic lupuserythematosus (SLE); and inflammatory diseases of the heart such ascardiomyopathy, ischemic heart disease hypercholesterolemia,atherosclerosis); as well as various other diseases with significantinflammatory components, including preeclampsia; chronic liver failure,brain and spinal cord trauma, cancer). There may also be a systemicinflammation of the body, exemplified by gram-positive or gram negativeshock, hemorrhagic or anaphylactic shock, or shock induced by cancerchemotherapy in response to pro-inflammatory cytokines, e.g., shockassociated with pro-inflammatory cytokines. Such shock can be induced,e.g., by a chemotherapeutic agent used in cancer chemotherapy.“Treatment of an inflammatory disorder” herein refers to administering acompound or a composition of the invention to a subject, who has aninflammatory disorder, a symptom of such a disorder or a predispositiontowards such a disorder, with the purpose to cure, relieve, alter,affect, or prevent the inflammatory disorder, the symptom of it, or thepredisposition towards it.

An “effective amount” is the quantity of compound in which a beneficialoutcome is achieved when the compound is administered to a subject oralternatively, the quantity of compound that possess a desired activityin-vivo or in-vitro. In the case of inflammatory disorders andautoimmune disorders, a beneficial clinical outcome includes reductionin the extent or severity of the symptoms associated with the disease ordisorder and/or an increase in the longevity and/or quality of life ofthe subject compared with the absence of the treatment. The preciseamount of compound administered to a subject will depend on the type andseverity of the disease or condition and on the characteristics of thesubject, such as general health, age, sex, body weight and tolerance todrugs. It will also depend on the degree, severity and type ofinflammatory disorder or autoimmune disorder or the degree ofimmunosuppression sought. The skilled artisan will be able to determineappropriate dosages depending on these and other factors. Effectiveamounts of the disclosed compounds typically range between about 1mg/mm² per day and about 10 grams/mm² per day, and preferably between 10mg/mm² per day and about 1 gram/mm².

The compounds of the invention may contain one or more chiral centersand/or double bonds and, therefore, exist as stereoisomers, such asdouble-bond isomers (i.e., geometric isomers), enantiomers, ordiastereomers. According to this invention, the chemical structuresdepicted herein, including the compounds of this invention, encompassall of the corresponding compounds' enantiomers and stereoisomers, thatis, both the stereomerically pure form (e.g., geometrically pure,enantiomerically pure, or diastereomerically pure) and enantiomeric,diastereomeric, and geometric isomeric mixtures. In some cases, oneenantiomer, diastereomer, or geometric isomer will possess superioractivity or an improved toxicity or kinetic profile compared to others.In those cases, such enantiomers, diastereomers, and geometric isomersof a compound of this invention are preferred.

The term “inhibit production of IL-2” and like terms means inhibitingIL-2 synthesis (e.g. by inhibiting transcription (mRNA expression), ortranslation (protein expression)) and/or inhibiting IL-2 secretion in acell that has the ability to produce and/or secrete IL-2 (e.g., Tlymphocyte). Likewise, the term “inhibiting production of IL-4, IL-5,IL-13, GM-CSF, TNF-α or INF-γ means inhibiting the synthesis (e.g. byinhibiting transcription, or translation) and/or inhibiting thesecretion in a cell that has the ability to produce and/or secrete thesecytokines.

As used herein, a composition that “substantially” comprises a compoundmeans that the composition contains more than about 80% by weight, morepreferably more than about 90% by weight, even more preferably more thanabout 95% by weight, and most preferably more than about 97% by weightof the compound.

As used herein, a composition that is “substantially free” of a compoundmeans that the composition contains less than about 20% by weight, morepreferably less than about 10% by weight, even more preferably less thanabout 5% by weight, and most preferably less than about 3% by weight ofthe compound.

As used herein, a reaction that is “substantially complete” means thatthe reaction contains more than about 80% by weight of the desiredproduct, more preferably more than about 90% by weight of the desiredproduct, even more preferably more than about 95% by weight of thedesired product, and most preferably more than about 97% by weight ofthe desired product.

As used herein, a racemic mixture means about 50% of one enantiomer andabout 50% of is corresponding enantiomer relative to all chiral centersin the molecule. The invention encompasses all enantiomerically-pure,enantiomerically-enriched, diastereomerically pure, diastereomericallyenriched, and racemic mixtures of the compounds of any one of formulas(I) through (II) or Table 1.

Enantiomeric and diastereomeric mixtures can be resolved into theircomponent enantiomers or stereoisomers by well known methods, such aschiral-phase gas chromatography, chiral-phase high performance liquidchromatography, crystallizing the compound as a chiral salt complex, orcrystallizing the compound in a chiral solvent. Enantiomers anddiastereomers can also be obtained from diastereomerically- orenantiomerically-pure intermediates, reagents, and catalysts by wellknown asymmetric synthetic methods.

When administered to a patient, e.g., to a non-human animal forveterinary use or for improvement of livestock, or to a human forclinical use, the compounds of the invention are typically administeredin isolated form or as the isolated form in a pharmaceuticalcomposition. As used herein, “isolated” means that the compounds of theinvention are separated from other components of either (a) a naturalsource, such as a plant or cell, preferably bacterial culture, or (b) asynthetic organic chemical reaction mixture. Preferably, viaconventional techniques, the compounds of the invention are purified. Asused herein, “purified” means that when isolated, the isolate containsat least 95%, preferably at least 98%, of a single compound of theinvention by weight of the isolate.

Only those choices and combinations of substituents that result in astable structure are contemplated. Such choices and combinations will beapparent to those of ordinary skill in the art and may be determinedwithout undue experimentation.

The invention can be understood more fully by reference to the followingdetailed description and illustrative examples, which are intended toexemplify non-limiting embodiments of the invention.

Specific Embodiments

The invention relates to compounds and pharmaceutical compositions thatare particularly useful for immunosuppression or to treat or preventinflammatory conditions, immune disorders, and allergic disorders.

One embodiment of the invention relates to compounds of formula (I):

-   -   or a pharmaceutically acceptable salt, solvate, clathrate, or        prodrug thereof, wherein:    -   Y is a monocyclic optionally substituted aryl or a monocyclic        optionally substituted heteroaryl;    -   L is a linker selected from the group consisting of —NRCR₂—,        —CR₂NR—, —C(O)—, —NR—C(O)—, —C(O)—NR—, —OC(O)—, —C(O)O—, —C(S)—,        —NR—C(S)—, —C(S)—NR—;    -   one of X₁ or X₂ is CH or CZ and the other is N;    -   each Z is independently selected from the group consisting of a        lower alkyl, a lower haloalkyl, a halo, a lower alkoxy, a lower        alkyl sulfanyl, —S(O)_(p)-alkyl, —C(O)NRR, —(CH₂)_(k)NRR,        —(CH₂)_(k)OR, —(CH₂)_(k)SR, cyano, nitro, or lower haloalkoxy;    -   R, for each occurrence is independently selected from —H or an        alkyl;    -   R₃ is H, an alkyl, a haloalkyl, a halo, a haloalkoxy, —OR₅,        —SR₅, or —NR₆R₇;    -   R₄ is a halo, a haloalkyl, cyano, nitro, —C(O)R₅, —C(O)OR₅,        —C(O)SR₅, —C(O)NR₉R₁₀, —C(S)R₅, —C(S)OR₅, —C(S)SR₅, —C(S)NR₆R₇,        —C(NR₈)R₅, —C(NR₈)OR₅, —C(NR₈)SR₅, —C(NR₈)NR₆R₇, —S(O)_(p)R₅,        —S(O)_(p)NR₅, —S(O)_(p)OR₅, —P(O)(OR₅)₂, —OP(O)(OR₅)₂,        —P(O)(R₅)₂, an optionally substituted heterocyclyl, or an        optionally substituted heteroaryl;    -   R₅, for each occurrence, is independently, H, an optionally        substituted alkyl, an optionally substituted alkenyl, an        optionally substituted alkynyl, an optionally substituted        cycloalkyl, an optionally substituted cycloalkenyl, an        optionally substituted heterocyclyl, an optionally substituted        aryl, an optionally substituted heteroaryl, an optionally        substituted aralkyl, or an optionally substituted heteraralkyl;    -   R₆ and R₇, for each occurrence are, independently, H, an        optionally substituted alkyl, an optionally substituted alkenyl,        an optionally substituted alkynyl, an optionally substituted        cycloalkyl, an optionally substituted cycloalkenyl, an        optionally substituted heterocyclyl, an optionally substituted        aryl, an optionally substituted heteroaryl, an optionally        substituted aralkyl, or an optionally substituted heteraralkyl;        or R₆ and R₇ taken together with the nitrogen to which they are        attached are an optionally substituted heterocyclyl or        optionally substituted heteroaryl;    -   R₈, for each occurrence, is independently —H, a halo, an alkyl,        —OR₅, —NR₆R₇, —C(O)R₅, —C(O)OR₅, or —C(O)NR₆R₇;    -   R₉ and R₁₀, for each occurrence are, independently, H, an        optionally substituted alkyl, an optionally substituted alkenyl,        an optionally substituted alkynyl, an optionally substituted 5-        to 14-membered cycloalkyl, an optionally substituted        cycloalkenyl, an optionally substituted heterocyclyl, an        optionally substituted aryl, an optionally substituted aralkyl,        an optionally substituted heteraralkyl, or an optionally        substituted heteroaryl selected from the group consisting of an        optionally substituted pyridinyl, an optionally substituted        thienyl, an optionally substituted pyrrolyl, an optionally        substituted oxazolyl, an optionally substituted imidazolyl, an        optionally substituted indolizinyl, an optionally substituted        isoxazolyl, an optionally substituted pyrazolyl, an optionally        substituted isothiazolyl, an optionally substituted pyridazinyl,        an optionally substituted pyrimidinyl, an optionally substituted        pyrazinyl, an optionally substituted triazinyl, an optionally        substituted triazolyl, an optionally substituted pyridinyl, an        optionally substituted thiadiazolyl, an optionally substituted        pyrazinyl, an optionally substituted quinolinyl, an optionally        substituted isoquinolinyl, an optionally substituted indazolyl,        an optionally substituted benzoxazolyl, an optionally        substituted benzofuryl, an optionally substituted        benzothiazolyl, an optionally substituted indolizinyl, an        optionally substituted imidazopyridinyl, an optionally        substituted tetrazolyl, an optionally substituted        benzimidazolyl, an optionally substituted benzoxazolyl, an        optionally substituted benzothiazolyl, an optionally substituted        benzothiadiazolyl, an optionally substituted benzoxadiazolyl, an        optionally substituted indolyl, an optionally substituted        tetrahydroindolyl, an optionally substituted azaindolyl, an        optionally substituted imidazopyridyl, an optionally substituted        qunizaolinyl, an optionally substituted purinyl, an optionally        substituted pyrrolo[2,3]pyrimidyl, an optionally substituted        pyrazolo[3,4]pyrimidyl or an optionally substituted        benzo(b)thienyl; or R₉ and R₁₀ taken together with the nitrogen        to which they are attached are an optionally substituted        heterocyclyl or optionally substituted heteroaryl;    -   q, for each occurrence, is independently, an integer from 1 to        3;    -   k is for each occurrence, is independently, an integer from 1 to        4;    -   n is zero, 1 or 2; and    -   p, for each occurrence, is independently 1 or 2.

Another embodiment of the invention relates to compounds of formula(II):

-   -   or a pharmaceutically acceptable salt, solvate, clathrate, or        prodrug thereof, wherein:    -   Y₁ is a monocyclic optionally substituted aryl or a monocyclic        optionally substituted heteroaryl, provided that Y₁ is not a        substituted isoxazolyl or a substituted 1H-pyrrolyl;    -   L₁ is a linker selected from the group consisting of —NHCH₂—,        —CH₂NH—, —NR—C(O)—, —OC(O)—, —C(O)O—, —C(S)—, —NR—C(S)—, or        —C(S)—NR—;    -   one of X₁ or X₂ is CH or CZ and the other is N;    -   each Z is independently selected from the group consisting of a        lower alkyl, a lower haloalkyl, a halo, a lower alkoxy, a lower        alkyl sulfanyl, —S(O)_(P)-alkyl, —C(O)NRR, —(CH₂)_(k)NRR,        —(CH₂)_(k)OR, —(CH₂)_(k)SR, cyano, nitro, or lower haloalkoxy;    -   R, for each occurrence is independently selected from —H or an        alkyl;    -   R₃ is H, an alkyl, a haloalkyl, a halo, a haloalkoxy, —OR₅,        —SR₅, or —NR₆R₇;    -   R₄ is a halo, a haloalkyl, cyano, nitro, —C(O)R₅, —C(O)OR₅,        —C(O)SR₅, —C(O)NR₉R₁₀, —C(S)R₅, —C(S)OR₅, —C(S)SR₅, —C(S)NR₆R₇,        —C(NR₈)R₅, —C(NR₈)OR₅, —C(NR₈)SR₅, —C(NR₈)NR₆R₇, —S(O)_(p)R₅,        —S(O)_(p)NR₅, —S(O)_(p)OR₅, —P(O)(OR₅)₂, —OP(O)(OR₅)₂,        —P(O)(R₅)₂, an optionally substituted heterocyclyl, or an        optionally substituted heteroaryl;    -   R₅, for each occurrence, is independently, H, an optionally        substituted alkyl, an optionally substituted alkenyl, an        optionally substituted alkynyl, an optionally substituted        cycloalkyl, an optionally substituted cycloalkenyl, an        optionally substituted heterocyclyl, an optionally substituted        aryl, an optionally substituted heteroaryl, an optionally        substituted aralkyl, or an optionally substituted heteraralkyl;    -   R₆ and R₇, for each occurrence are, independently, H, an        optionally substituted alkyl, an optionally substituted alkenyl,        an optionally substituted alkynyl, an optionally substituted        cycloalkyl, an optionally substituted cycloalkenyl, an        optionally substituted heterocyclyl, an optionally substituted        aryl, an optionally substituted heteroaryl, an optionally        substituted aralkyl, or an optionally substituted heteraralkyl;        or R₆ and R₇ taken together with the nitrogen to which they are        attached are an optionally substituted heterocyclyl or        optionally substituted heteroaryl;    -   R₈, for each occurrence, is independently —H, a halo, an alkyl,        —OR₅, —NR₆R₇, —C(O)R₅, —C(O)OR₅, or —C(O)NR₆R₇;    -   R₉ and R₁₀, for each occurrence are, independently, H, an        optionally substituted alkyl, an optionally substituted alkenyl,        an optionally substituted alkynyl, an optionally substituted 5-        to 14-membered cycloalkyl, an optionally substituted        cycloalkenyl, an optionally substituted heterocyclyl, an        optionally substituted aryl, an optionally substituted aralkyl,        an optionally substituted heteraralkyl, or an optionally        substituted heteroaryl selected from the group consisting of an        optionally substituted pyridinyl, an optionally substituted        thienyl, an optionally substituted pyrrolyl, an optionally        substituted oxazolyl, an optionally substituted imidazolyl, an        optionally substituted indolizinyl, an optionally substituted        isoxazolyl, an optionally substituted pyrazolyl, an optionally        substituted isothiazolyl, an optionally substituted pyridazinyl,        an optionally substituted pyrimidinyl, an optionally substituted        pyrazinyl, an optionally substituted triazinyl, an optionally        substituted triazolyl, an optionally substituted pyridinyl, an        optionally substituted thiadiazolyl, an optionally substituted        pyrazinyl, an optionally substituted quinolinyl, an optionally        substituted isoquinolinyl, an optionally substituted indazolyl,        an optionally substituted benzoxazolyl, an optionally        substituted benzofuryl, an optionally substituted        benzothiazolyl, an optionally substituted indolizinyl, an        optionally substituted imidazopyridinyl, an optionally        substituted tetrazolyl, an optionally substituted        benzimidazolyl, an optionally substituted benzoxazolyl, an        optionally substituted benzothiazolyl, an optionally substituted        benzothiadiazolyl, an optionally substituted benzoxadiazolyl, an        optionally substituted indolyl, an optionally substituted        tetrahydroindolyl, an optionally substituted azaindolyl, an        optionally substituted imidazopyridyl, an optionally substituted        qunizaolinyl, an optionally substituted purinyl, an optionally        substituted pyrrolo[2,3]pyrimidyl, an optionally substituted        pyrazolo[3,4]pyrimidyl or an optionally substituted        benzo(b)thienyl; or R₉ and R₁₀ taken together with the nitrogen        to which they are attached are an optionally substituted        heterocyclyl or optionally substituted heteroaryl;    -   q, for each occurrence, is independently, an integer from 1 to        3;    -   k is for each occurrence, is independently, an integer from 1 to        4;    -   n is zero, 1 or 2; and    -   p, for each occurrence, is independently 1 or 2.

In one embodiment, in compounds represented by formula (I) or (II), X₁is N. In one aspect, X₂ is CH. In one aspect, X₂ is C(CH₃).

In one embodiment, in compounds represented by formula (I) or (II), X₂is N. In one aspect, X₁ is CH. In one aspect, X₁ is C(CH₃).

In one embodiment, in compounds represented by formula (I) or (II), X₁is N; X₂ is CH; Z is methyl; and n is 1.

In one embodiment, in compounds represented by formula (I) or (II), X₂is N; X₁ is CH; Z is methyl; and n is 1.

In one embodiment, in compounds represented by formula (I) or (II), n is0.

In one embodiment, in compounds represented by formula (I) or (II), n is1 and Z is chloro, fluoro, bromo, methyl, methoxy, cyano, nitro,methylsulfanyl, or trifluoromethyl. In one aspect, Z is methyl.

In one embodiment, in compounds represented by formula (I) or (II), n is2 and each Z is independently chloro, fluoro, bromo, methyl, methoxy,cyano, nitro, methylsulfanyl, or trifluoromethyl.

In one embodiment, in compounds represented by formula (I) or (II), Z ischloro, fluoro, bromo, methyl, methoxy, cyano, nitro, methylsulfanyl, ortrifluoromethyl. In one aspect, Z is methyl.

In one embodiment, in compounds represented by formula (I) or (II), R₄is —C(O)OR₅, a haloalkyl, an optionally substituted oxazolyl, anoptionally substituted isoxazolyl, an optionally substituted thiazolyl,an optionally substituted imidazolyl, an optionally substitutedpyridinyl, an optionally substituted pyrazolyl, an optionallysubstituted pyrrolyl, an optionally substituted thiophenyl, anoptionally substituted furanyl, an optionally substituted thiadiazolyl,an optionally substituted oxadiazolyl, or an optionally substitutedtetrazolyl. In another aspect, R₄ is —C(O)OR₅, a haloalkyl, anoptionally substituted oxazolyl, an optionally substituted thiazolyl, anoptionally substituted imidazolyl, an optionally substituted pyridinyl,an optionally substituted pyrazolyl, an optionally substituted pyrrolyl,an optionally substituted thiophenyl, an optionally substituted furanyl,an optionally substituted thiadiazolyl, an optionally substitutedoxadiazolyl, or an optionally substituted tetrazolyl. In one aspect, R₄is oxazol-2-yl, oxazol-5-yl, 3-methyl-isoxazol-5-yl, isoxazol-5-yl,thiazol-2-yl, thiazol-5-yl, [1,3,4]oxadiazol-2-yl,[1,3,4]thiadiazol-2-yl, trifluoromethyl, pyridin-3-yl, pyridin-2-yl,furan-2-yl, furan-3-yl, thiophen-2-yl, thiophen-3-yl, —C(O)OCH₂CH₂OCH₃,—C(O)OCH₂CH₂CH₃, —C(O)OCH₂CH₃, or —C(O)OCH₃. In one aspect, R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, thiazol-5-yl,[1,3,4]oxadiazol-2-yl, trifluoromethyl, pyridin-3-yl, pyridin-2-yl,—C(O)OCH₂CH₂CH₃, —C(O)OCH₂CH₃, or —C(O)OCH₃. In one aspect, R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, trifluoromethyl, or —C(O)OCH₃.In one aspect, R₄ is oxazol-2-yl. In one aspect, R₄ is oxazol-5-yl. Inone aspect, R₄ is thiazol-2-yl. In one aspect, R₄ is thiazol-5-yl. Inone aspect, R₄ is [1,3,4]oxadiazol-2-yl. In one aspect, R₄ istrifluoromethyl. In one aspect, R₄ is pyridin-3-yl. In one aspect, R₄ ispyridin-2-yl. In one aspect, R₄ is —C(O)OCH₂CH₂CH₃, —C(O)OCH₂CH₃, or—C(O)OCH₃. In one aspect, R₄ is —C(O)OCH₃.

In one embodiment, in compounds represented by formula (I) or (II), R₄is a biostere of an ester, amide, or carboxylic acid.

In one embodiment, in compounds represented by formula (I) or (II), R₃is —H, chloro, fluoro, bromo, methyl, or methoxy. In one aspect, R₃ is—H, chloro, methyl, or methoxy. In one aspect, R₃ is —H. In one aspect,R₃ is chloro. In one aspect, R₃ is fluoro. In one aspect, R₃ is bromo.In one aspect, R₃ is methyl. In one aspect, R₃ is methoxy.

In one embodiment, in compounds represented by formula (I), Y is anoptionally substituted phenyl, an optionally substituted pyridinyl, anoptionally substituted pyrazolyl, an optionally substituted pyridazinyl,an optionally substituted isothiazolyl, an optionally substitutedthiazolyl, an optionally substituted triazolyl, an optionallysubstituted oxadiazolyl, an optionally substituted oxazolyl, anoptionally substituted isoxazolyl, an optionally substitutedthiadiazolyl, or an optionally substituted thiophenyl. In anotheraspect, Y is an optionally substituted phenyl, an optionally substitutedpyridinyl, an optionally substituted pyridazinyl, an optionallysubstituted isothiazolyl, an optionally substituted thiazolyl, anoptionally substituted triazolyl, an optionally substituted oxadiazolyl,an optionally substituted oxazolyl, an optionally substitutedisoxazolyl, an optionally substituted thiadiazolyl, or an optionallysubstituted thiophenyl. In one aspect, Y is an optionally substitutedphenyl or an optionally substituted thiadiazolyl. In one aspect, Y is anoptionally substituted phenyl. In one aspect, Y is a phenyl substitutedwith one to two substituents. In one aspect, Y is a phenyl substitutedwith one to two substituents, wherein the one to two substituents areeach independently a lower alkyl or a halo. In one aspect, Y is2,6-difluorophenyl or 4-methyl-1,2,3-thiadiazol-5-yl. In one aspect, Yis a difluorophenyl. In one aspect, Y is 2,6-difluorophenyl. In oneaspect, Y is 4-methyl-1,2,3-thiadiazol-5-yl. In one aspect, Y is anoptionally substituted pyridinyl. In one aspect, Y is an optionallysubstituted triazolyl. In one aspect, Y is an optionally substitutedoxadiazolyl. In one aspect, Y is an optionally substituted thiazolyl. Inone aspect, Y is an optionally substituted oxazolyl. In one aspect, Y isan optionally substituted isoxazolyl. In one aspect, Y is amono-substituted pyridinyl. In one aspect, Y is a methylpyridin-2yl or afluoro pyridin-2yl.

In one embodiment, in compounds represented by formula (I), L is alinker selected from the group consisting of —NHCH₂—, —CH₂NH—, —C(O)—,—NH—C(O)—, —C(O)—NH—, —OC(O)—, —C(O)O—, —C(S)—, —NH—C(S)—, —C(S)—NH—. Inone aspect, L is —NHCH₂—. In one aspect, L is —CH₂NH—. In one aspect, Lis —C(O)—. In one aspect, L is —C(O)—NH—. In one aspect, L is —OC(O)—.In one aspect, L is —C(O)O—. In one aspect, L is —C(S)—. In one aspect,L is —NH—C(S)—. In one aspect, L is —C(S)—NH—.

In one embodiment, in compounds represented by formula (I), L is—NR—C(O)—. In one aspect, L is —NH—C(O)—.

In one embodiment, in compounds represented by formula (I), Y is anoptionally substituted phenyl, an optionally substituted pyridinyl, anoptionally substituted pyridazinyl, an optionally substitutedisothiazolyl, an optionally substituted thiazolyl, an optionallysubstituted triazolyl, an optionally substituted oxadiazolyl, anoptionally substituted oxazolyl, an optionally substituted thiadiazolyl,or an optionally substituted thiophenyl; R₄ is —C(O)OR₄, a haloalkyl, anoptionally substituted oxazolyl, an optionally substituted thiazolyl, anoptionally substituted imidazolyl, an optionally substituted pyridinyl,an optionally substituted pyrazolyl, an optionally substituted pyrrolyl,an optionally substituted thiophenyl, an optionally substituted furanyl,an optionally substituted thiadiazolyl, an optionally substitutedoxadiazolyl, or an optionally substituted tetrazolyl; one of X₁ or X₂ isCH; and n is 0. In one aspect, L is —NH—C(O)—. In one aspect, R₃ is —H,chloro, fluoro, bromo, methyl, or methoxy. In one aspect, R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, thiazol-5-yl,[1,3,4]oxadiazol-2-yl, trifluoromethyl, pyridin-3-yl, pyridin-2-yl,—C(O)OCH₂CH₂CH₃, —C(O)OCH₂CH₃, or —C(O)OCH₃. In one aspect, Y is adifluorophenyl. In one aspect, Y is 4-methyl-1,2,3-thiadiazol-5-yl.

In one embodiment, in compounds represented by formula (I), Y is2,6-difluorophenyl or 4-methyl-1,2,3-thiadiazol-5-yl; L is —NH—C(O)—;one of X₁ or X₂ is CH; R₃ is —H, chloro, methyl, or methoxy; R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, trifluoromethyl, or —C(O)OCH₃;and n is 0.

In one embodiment, in compounds represented by formula (II), Y₁ is anoptionally substituted phenyl, an optionally substituted pyridinyl, anoptionally substituted pyrazolyl, an optionally substituted pyridazinyl,an optionally substituted isothiazolyl, an optionally substitutedthiazolyl, an optionally substituted triazolyl, an optionallysubstituted oxadiazolyl, an optionally substituted oxazolyl, anoptionally substituted isoxazolyl, an optionally substitutedthiadiazolyl, or an optionally substituted thiophenyl. In anotheraspect, Y₁ is an optionally substituted phenyl, an optionallysubstituted pyridinyl, an optionally substituted pyridazinyl, anoptionally substituted isothiazolyl, an optionally substitutedthiazolyl, an optionally substituted triazolyl, an optionallysubstituted oxadiazolyl, an optionally substituted oxazolyl, anoptionally substituted thiadiazolyl, or an optionally substitutedthiophenyl. In one aspect, Y₁ is an optionally substituted phenyl or anoptionally substituted thiadiazolyl. In one aspect, Y₁ is an optionallysubstituted phenyl. In one aspect, Y₁ is a phenyl substituted with oneto two substituents.

In one aspect, Y₁ is a phenyl substituted with one to two substituents,wherein the one to two substituents are each independently a lower alkylor a halo. In one aspect, Y₁ is 2,6-difluorophenyl or4-methyl-1,2,3-thiadiazol-5-yl. In one aspect, Y₁ is a difluorophenyl.In one aspect, Y₁ is 2,6-difluorophenyl. In one aspect, Y₁ is4-methyl-1,2,3-thiadiazol-5-yl. In one aspect, Y₁ is an optionallysubstituted pyridinyl. In one aspect, Y₁ is an optionally substitutedtriazolyl. In one aspect, Y₁ is an optionally substituted oxadiazolyl.In one aspect, Y₁ is an optionally substituted thiazolyl. In one aspect,Y₁ is an optionally substituted oxazolyl. In one aspect, Y₁ is amono-substituted pyridinyl. In one aspect, Y₁ is a methylpyridin-2yl ora fluoro pyridin-2yl.

In one embodiment, in compounds represented by formula (II), L₁ is alinker selected from the group consisting of —NHCH₂—, —CH₂NH—,—NH—C(O)—, —OC(O)—, —C(O)O—, —C(S)—, —NH—C(S)—, or —C(S)—NH—. In oneaspect, L₁ is —NHCH₂—. In one aspect, L₁ is —CH₂NH—. In one aspect, L₁is —OC(O)—. In one aspect, L₁ is —C(O)O—. In one aspect, L₁ is —C(S)—.In one aspect, L₁ is —NH—C(S)—. In one aspect, L₁ is —C(S)—NH—.

In one embodiment, in compounds represented by formula (II), L₁ is—NR—C(O)—. In one aspect, is —NH—C(O)—.

In one embodiment, in compounds represented by formula (II), Y₁ is anoptionally substituted phenyl, an optionally substituted pyridinyl, anoptionally substituted pyridazinyl, an optionally substitutedisothiazolyl, an optionally substituted thiazolyl, an optionallysubstituted triazolyl, an optionally substituted oxadiazolyl, anoptionally substituted oxazolyl, an optionally substituted thiadiazolyl,or an optionally substituted thiophenyl; R₄ is —C(O)OR₄, a haloalkyl, anoptionally substituted oxazolyl, an optionally substituted thiazolyl, anoptionally substituted imidazolyl, an optionally substituted pyridinyl,an optionally substituted pyrazolyl, an optionally substituted pyrrolyl,an optionally substituted thiophenyl, an optionally substituted furanyl,an optionally substituted thiadiazolyl, an optionally substitutedoxadiazolyl, or an optionally substituted tetrazolyl; one of X₁ or X₂ isCH; and n is 0. In one aspect, L₁ is —NH—C(O)—. In one aspect, R₃ is —H,chloro, fluoro, bromo, methyl, or methoxy. In one aspect, R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, thiazol-5-yl,[1,3,4]oxadiazol-2-yl, trifluoromethyl, pyridin-3-yl, pyridin-2-yl,—C(O)OCH₂CH₂CH₃, —C(O)OCH₂CH₃, or —C(O)OCH₃. In one aspect, Y₁ is adifluorophenyl. In one aspect, Y₁ is 4-methyl-1,2,3-thiadiazol-5-yl.

In one embodiment, in compounds represented by formula (II), Y₁ is2,6-difluorophenyl or 4-methyl-1,2,3-thiadiazol-5-yl; L₁ is —NH—C(O)—;one of X₁ or X₂ is CH; R₃ is —H, chloro, methyl, or methoxy; R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, trifluoromethyl, or —C(O)OCH₃;and n is 0.

In another embodiment, the invention relates to compounds selected fromthe group consisting of:

-   N-[6-(2-chloro-5-trifluoromethyl-phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide;-   N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;-   N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide;-   N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-3-fluoro-isonicotinamide;-   2,6-Difluoro-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;-   4-Chloro-3-[6-(2,6-difluoro-benzoylamino)-pyridin-3-yl]-benzoic acid    methyl ester;-   3-[6-(2,6-Difluoro-benzoylamino)-pyridin-3-yl]-4-methyl-benzoic acid    methyl ester;-   N-[5-(2-Chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;-   N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-6-methyl-pyridin-2-yl]-2,6-difluoro-benzamide;-   N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;-   N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-4-methyl-pyridin-2-yl]-2,6-difluoro-benzamide;-   3-[5-(2,6-Difluoro-benzoylamino)-pyridin-2-yl]-4-methyl-benzoic acid    methyl ester;-   2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]benzamide;-   2,6-Difluoro-N-[4-methyl-5-(3-trifluoromethyl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N4-[6-methyl-5-(3-trifluoromethyl-phenyl)-pyridin-2-yl]-benzamide;-   4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid    [5-(2-chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-amide;-   4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid    [5-(2-chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-amide;-   4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid    [5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;-   4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid    [5-(2-chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;-   2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide    hydrochloride;-   4-methyl-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-1,2,3-thiadiazole-5-carboxamide;-   3-(6-Benzoylamino-pyridin-3-yl)-4-chloro-benzoic acid methyl ester;-   4-Chloro-3-[6-(2-methyl-benzoylamino)-pyridin-3-yl]-benzoic acid    methyl ester;-   4-Chloro-3-{6-[(3-methyl-pyridine-4-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(3-fluoro-pyridine-4-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(3-chloro-pyridine-4-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(4-methyl-[1,2,3]thiadiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(4-methyl-[1,2,3]oxadiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(5-methyl-3H-[1,2,3]triazole-4-carbonyl)-amino}-pyridin-3-yl]-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(4-methyl-isothiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(4-methyl-thiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(4-methyl-oxazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(4-methyl-isoxazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(2-methyl-2H-pyrazole-3-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   4-Chloro-3-{6-[(4-fluoro-isothiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic    acid methyl ester;-   3-Methyl-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;-   3-Methyl-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;-   2,6-Difluoro-N-[5-methyl-6-(3-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;-   2,6-Difluoro-N4-[4-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N4-[6-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;-   3-Methyl-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;-   3-Methyl-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;-   2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;-   2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide    hydrochloride;-   N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide;-   N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-3-methyl-isonicotinamide;-   N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide;-   3-[5-(2,6-Difluoro-benzoylamino)-pyridin-2-yl]-4-methyl-benzoic acid    ethyl ester;-   3-[6-(2,6-Difluoro-benzoylamino)-pyridin-3-yl]-4-methyl-benzoic acid    ethyl ester;-   2,6-Difluoro-N-[5-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N-[6-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-3-yl]-benzamide;-   2,6-Difluoro-N-[6-(5-isoxazol-5-yl-2-methyl-phenyl)-pyridin-3-yl]-benzamide;-   2,6-Difluoro-N-[5-(5-isoxazol-5-yl-2-methyl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N-{5-[2-methyl-5-(3-methyl-isoxazol-5-yl)-phenyl]-pyridin-2-yl}-benzamide;-   2,6-Difluoro-N-{6-[2-methyl-5-(3-methyl-isoxazol-5-yl)-phenyl]-pyridin-3-yl}-benzamide;-   2,6-Difluoro-N-[6-(2-methyl-5-pyridin-3-yl-phenyl)-pyridin-3-yl]-benzamide;-   2,6-Difluoro-N-[6-(2-methyl-5-pyridin-2-yl-phenyl)-pyridin-3-yl]benzamide;-   2,6-Difluoro-N-[5-(2-methyl-[1,3,4]oxadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]thiadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;-   4-Chloro-3-[6-(2,6-difluoro-benzoylamino)-pyridin-3-yl]-benzoic acid    propyl ester;-   4-Chloro-3-[6-(2,6-difluoro-benzoylamino)-pyridin-3-yl]-benzoic acid    2-methoxy-ethyl ester;-   2,6-Difluoro-N-[5-(5-furan-2-yl-2-methyl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N-[5-(2-methyl-5-thiophen-2-yl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N-[5-(5-furan-3-yl-2-methyl-phenyl)-pyridin-2-yl]-benzamide;-   2,6-Difluoro-N-[5-(2-methyl-5-thiophen-3-yl-phenyl)-pyridin-2-yl]-benzamide;-   N-(5-(2-methoxy-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamide;-   N-(5-(5-(isoxazol-5-yl)-2-methylphenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamide-   2,6-difluoro-N-(5-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)benzamide;-   2,6-difluoro-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)benzamide;-   N-(5-(2-chloro-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)-2,6-difluorobenzamide;-   N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;-   N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide    hydrochloric acid salt;-   2,6-Difluoro-N-(6-(2-methyl-5-(thiazol-2-yl)phenyl)pyridin-3-yl)benzamide;-   2,6-Difluoro-N-(6-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-3-yl)benzamide;-   N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;-   N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide    hydrochloric acid salt;-   2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamide;-   2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamide    hydrochloric acid salt; or-   4-chloro-2-fluoro-N-(6-(2-methyl-5-(oxazol-2-yl)phenyl)pyridin-3-yl)benzamide;    -   or a pharmaceutically acceptable salt, solvate, clathrate, or        prodrug thereof.

All of the features, specific embodiments and particular substituentsdisclosed herein may be combined in any combination. Each feature,embodiment or substituent disclosed in this specification may bereplaced by an alternative feature, embodiment or substituent servingthe same, equivalent, or similar purpose. In the case of chemicalcompounds, specific values for variables (e.g., values shown in theexemplary compounds disclosed herein) in any chemical formula disclosedherein can be combined in any combination resulting in a stablestructure. Furthermore, specific values (whether preferred or not) forsubstituents in one type of chemical structure may be combined withvalues for other substituents (whether preferred or not) in the same ordifferent type of chemical structure. Thus, unless expressly statedotherwise, each feature, embodiment or substituent disclosed is only anexample of a generic series of equivalent or similar features,embodiments or substituents.

In another embodiment, the invention relates to pharmaceuticalcompositions that comprise a compound of any one of formulas (I) through(II), or Table 1, or a pharmaceutically acceptable salt, solvate,clathrate, or prodrug thereof, as an active ingredient, and apharmaceutically acceptable carrier or vehicle. The compositions areuseful for immunosuppression or to treat or prevent inflammatoryconditions, allergic conditions and immune disorders.

In another embodiment, the invention relates to methods forimmunosuppression or for treating or preventing inflammatory conditions,immune disorders, or allergic disorders in a patient in need thereofcomprising administering an effective amount of a compound representedby any one of formulas (I) through (It), or Table 1, or apharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof.

In another embodiment, the invention relates to methods forimmunosuppression or for treating or preventing inflammatory conditions,immune disorders, or allergic disorders in a patient in need thereofcomprising administering an effective amount of a pharmaceuticalcomposition that comprises a compound represented by any one of formulas(I) through (II), or in or Table 1, or a pharmaceutically acceptablesalt, solvate, clathrate, or prodrug thereof.

In another embodiment, compounds of any one of formulas (I) through(II), or Table 1, or a pharmaceutically acceptable salt, solvate,clathrate, or prodrug thereof, are particularly useful inhibiting immunecell (e.g., T-cells and/or B-cells) activation (e.g., activation inresponse to an antigen) and/or T cell and/or B cell proliferation.Indicators of immune cell activation include secretion of IL-2 by Tcells, proliferation of T cells and/or B cells, and the like. In oneembodiment, a compound of any one of formulas (I) through (II) or Table1, inhibits immune cell activation and/or T cell and/or B cellproliferation in a mammal (e.g., a human).

In another embodiment, compounds of any one of formula (I) through (II),or Table 1, or a pharmaceutically acceptable salt, solvate, clathrate,or prodrug thereof, can inhibit the production of certain cytokines thatregulate immune cell activation. For example, compounds of any one offormulas (I) through (II), or Table 1, or a pharmaceutically acceptablesalt, solvate, clathrate, or prodrug thereof, can inhibit the productionof IL-2, IL-4, IL-5, IL-13, GM-CSF, IFN-γ, TNF-α and combinationsthereof. In one embodiment, a compound of any one of formulas (I)through (II), or Table 1, inhibits cytokine production in a mammal(e.g., a human).

In another embodiment, compounds of any one of formulas (I) through(II), or Table 1, or a pharmaceutically acceptable salt, solvate,clathrate, or prodrug thereof, can modulate the activity of one or moreion channel involved in activation of immune cells, such as CRAC ionchannels. In one embodiment, a compound of any one of formulas (I)through (II) or Table 1 can inhibit the influx of calcium ions into animmune cell (e.g., T cells and/or B cells) by inhibiting the action ofCRAC ion channels. In general, a decrease in I_(CRAC) current uponcontacting a cell with a compound is one indicator that the compoundinhibitions CRAC ion channels. I_(CRAC) current can be measured, forexample, using a patch clamp technique, which is described in moredetail in the examples below. In one embodiment, a compound of any oneof formulas (I) through (II) or Table 1 modulates an ion channel in amammal (e.g., a human).

Exemplary Compounds of the Invention

Exemplary compounds of the invention are depicted in Table 1 below.

TABLE 1 Compound No. Structure Chemical Name 1

N-[6-(2-chloro-5- trifluoromethyl-phenyl)- pyridin-3-yl]-2,6-difluoro-benzamide 2

N-[5-(2-Chloro-5- trifluoromethyl-phenyl)- pyridin-2-yl]-2,6-difluoro-benzamide 3

N-[5-(2-Chloro-5- trifluoromethyl-phenyl)- pyridin-2-yl]-3-methyl-isonicotinamide 4

N-[5-(2-Chloro-5- trifluoromethyl-phenyl)- pyridin-2-yl]-3-fluoro-isonicotinamide 5

2,6-Difluoro-N-[5-(2-methyl-5- oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide 6

4-Chloro-3-[6-(2,6-difluoro- benzoylamino)-pyridin-3-yl]- benzoic acidmethyl ester 7

3-[6-(2,6-Difluoro- benzoylamino)-pyridin-3-yl]-4- methyl-benzoic acidmethyl ester 8

N-[5-(2-Chloro-5-oxazol-2-yl- phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide 9

N-[5-(2-Chloro-5- trifluoromethyl-phenyl)-6- methyl-pyridin-2-yl]-2,6-difluoro-benzamide 10

N-[5-(2-Chloro-5-thiazol-2-yl- phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide 11

N-[5-(2-Chloro-5- trifluoromethyl-phenyl)-4- methyl-pyridin-2-yl]-2,6-difluoro-benzamide 12

3-[6-(2,6-Difluoro- benzoylamino)-pyridin-2-yl]-4- methyl-benzoic acidmethyl ester 13

2, 6-Difluoro-N-[6-(2-methyl-5- oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide 14

2,6-Difluoro-N-[4-methyl-5-(3- trifluoromethyl-phenyl)-pyridin-2-yl]-benzamide 15

2,6-Difluoro-N-[6-methyl-5-(3- trifluoromethyl-phenyl)-pyridin-2-yl]-benzamide 16

4-Methyl-[1,2,3]thiadiazole-5- carboxylic acid[5-(2-chloro-5-trifluoromethyl- phenyl)-pyridin-2-yl]-amide 17

4-Methyl-[1,2,3]thiadiazole-5- carboxylic acid[5-(2-chloro-5-thiazol-2-yl- phenyl)-pyridin-2-yl]-amide 18

4-Methyl-[1,2,3]thiadiazole-5- carboxylic acid[5-(2-methyl-5-oxazol-2-yl- phenyl)-pyridin-2-yl]-amide 19

4-Methyl-[1,2,3]thiadiazole-5- carboxylic acid[5-(2-chloro-5-oxazol-2-yl- phenyl)-pyridin-2-yl]-amide 20

2,6-Difluoro-N-[6-(2-methyl-5- oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide hydrochloride 21

4-methyl-N-(5-(2-methyl-5- (oxazol-5-yl)phenyl)pyridin-2-yl)-1,2,3-thiadiazole-5- carboxamide 22

3-(6-Benzoylamino-pyridin-3- yl)-4-chloro-benzoic acid methyl ester 23

4-Chloro-3-[6-(2-methyl- benzoylamino)-pyridin-3-yl]- benzoic acidmethyl ester 24

4-Chloro-3-{6-[(3-methyl- pyridine-4-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 25

4-Chloro-3-{6-[(3-fluoro- pyridine-4-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 26

4-Chloro-3-{6-[(3-chloro- pyridine-4-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 27

4-Chloro-3-{6-[(4-methyl-[1,2,3] thiadiazole-5-carbonyl)-amino]-pyridin-3-yl}benzoic acid methyl ester 28

4-Chloro-3-{6-[(4-methyl-[1,2,3] oxadiazole-5-carbonyl)-amino]-pyridin-3-yl}benzoic acid methyl ester 29

4-Chloro-3-{6-[(4-methyl-[1,2,3] triazole-4-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 30

4-Chloro-3-{6-[(4-methyl- isothiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 31

4-Chloro-3-{6-[(4-methyl- thiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 32

4-Chloro-3-{6-[(4-methyl- oxazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 33

4-Chloro-3-{6-[(4-methyl- isoxazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 34

4-Chloro-3-{6-[(2-methyl-2H- pyrazole-3-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 35

4-Chloro-3-{6-[(4-fluoro- isothiazole-5-carbonyl)-amino]-pyridin-3-yl}-benzoic acid methyl ester 36

3-Methyl-N-[5-(2-methyl-5- oxazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide 37

3-Methyl-N-[6-(2-methyl-5- oxazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide 38

2,6-Difluoro-N-[5-methyl-6-(3- oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide 39

2,6-Difluoro-N-[4-methyl-5-(3- oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide 40

2,6-Difluoro-N-[6-methyl-5-(3- oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide 41

2,6-Difluoro-N-[5-(2-methyl-5- thiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide 42

3-Methyl-N-[5-(2-methyl-5- thiazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide 43

3-Methyl-N-[6-(2-methyl-5- thiazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide 44

2,6-Difluoro-N-[6-(2-methyl-5- thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide 45

2,6-Difluoro-N-[6-(2-methyl-5- thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide hydrochloride 46

N-[5-(2-Chloro-5-thiazol-2-yl- phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide 47

N-[6-(2-Chloro-5-thiazol-2-yl- phenyl)-pyridin-3-yl]-3-methyl-isonicotinamide 48

N-[6-(2-Chloro-5-thiazol-2-yl- phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide 49

3-[5-(2,6-Difluoro- benzoylamino)-pyridin-2-yl]-4- methyl-benzoic acidethyl ester 50

3-[6-(2,6-Difluoro- benzoylamino)-pyridin-3-yl]-4- methyl-benzoic acidethyl ester 51

2,6-Difluoro-N-[5-(2-methyl-5- oxazol-5-yl-phenyl)-pyridin-2-yl]-benzamide 52

2,6-Difluoro-N-[6-(2-methyl-5- oxazol-5-yl-phenyl)-pyridin-3-yl]-benzamide 53

2,6-Difluoro-N-[6-(5-isoxazol- 5-yl-2-methyl-phenyl)-pyridin-3-yl]-benzamide 54

2,6-Difluoro-N-[5-(5-isoxazol- 5-yl-2-methyl-phenyl)-pyridin-2-yl]-benzamide 55

2,6-Difluoro-N-{5-[2-methyl-5- (3-methyl-isoxazol-5-yl)-phenyl]-pyridin-2- yl}-benzamide 56

2,6-Difluoro-N-{6-[2-methyl-5- (3-methyl-isoxazol-5-yl)-phenyl]-pyridin- 3-yl}-benzamide 57

2,6-Difluoro-N-[6-(2-methyl-5- pyridin-3-yl-phenyl)-pyridin-3-yl]-benzamide 58

2,6-Difluoro-N-[6-(2-methyl-5- pyridin-2-yl-phenyl)-pyridin-3-yl]-benzamide 59

2,6-Difluoro-N-[5-(2-methyl-5- [1,3,4]oxadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide 60

2,6-Difluoro-N-[5-(2-methyl-5- [1,3,4]thiadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide 61

4-Chloro-3-[6-(2,6-difluoro- benzoylamino)-pyridin-3-yl]- benzoic acidpropyl ester 62

4-Chloro-3-[6-(2,6-difluoro- benzoylamino)-pyridin-3-yl]- benzoic acid2-methoxy-ethyl ester 63

2,6-Difluoro-N-[5-(5-furan-2- yl-2-methyl-phenyl)-pyridin-2-yl]-benzamide 64

2,6-Difluoro-N-[5-(2-methyl-5- thiophen-2-yl-phenyl)-pyridin-2-yl]-benzamide 65

2,6-Difluoro-N-[5-(5-furan-3- yl-2-methyl-phenyl)-pyridin-2-yl]-benzamide 66

2,6-Difluoro-N-[5-(2-methyl-5- thiophen-3-yl-phenyl)-pyridin-2-yl]-benzamide 67

N-(5-(2-methoxy-5-(oxazol-5- yl)phenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5- carboxamide 68

N-(5-(5-(isoxazol-5-yl)-2- methylphenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5- carboxamide 69

2,6-difluoro-N-(5-(2-methyl-5- (1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)benzamide 70

2,6-difluoro-N-(5-(2-methyl-5- (oxazol-5-yl)phenyl) pyridin-2-yl)benzamide 71

N-(5-(2-chloro-5-(1,3,4- oxadiazol-2-yl)phenyl)pyridin-2-yl)-2,6-difluorobenzamide 72

N-(6-(2-chloro-5-(thiazol-2-yl) phenyl)pyridin-3-yl)-2,6-difluorobenzamide 73

N-(6-(2-chloro-5-(thiazol-2-yl) phenyl)pyridin-3-yl)-2,6-difluorobenzamide hydrochloric acid salt 74

2,6-Difluoro-N-(6-(2-methyl-5- (thiazol-2-yl)phenyl)pyridin-3-yl)benzamide 75

2,6-Difluoro-N-(6-(2-methyl-5- (1,3,4-oxadiazol-2-yl)phenyl)pyridin-3-yl)benzamide 76

N-(6-(2-chloro-5-(oxazol-2-yl) phenyl)pyridin-3-yl)-2,6-difluorobenzamide 77

N-(6-(2-chloro-5-(oxazol-2-yl) phenyl)pyridin-3-yl)-2,6-difluorobenzamide hydrochloric acid salt 78

2,6-Difluoro-N-(6-(2-methyl-5- (oxazol-5-yl)phenyl)pyridin-3-yl)benzamide 79

2,6-Difluoro-N-(6-(2-methyl-5- (oxazol-5-yl)phenyl)pyridin-3-yl)benzamide hydrochloric acid salt 80

4-chloro-2-fluoro-N-(6-(2- methyl-5-(oxazol-2-yl)phenyl)pyridin-3-yl)benzamideMechanism of Action

Activation of T-lymphocytes in response to an antigen is dependent oncalcium ion oscillations. Calcium ion oscillations in T-lymphocytes aretriggered through stimulation of the T-cell antigen receptor, andinvolve calcium ion influx through the stored-operatedCa²⁺-release-activated Ca²⁺ (CRAC) channel. Although the molecularstructure of the CRAC ion channel has not been identified, a detailedelectrophysiological profile of the channel exist. Thus, inhibition ofCRAC ion channels can be measured by measuring inhibition of theI_(CRAC) current. Calcium ion oscillations in T-cells have beenimplicated in the activation of several transcription factors (e.g.,NFAT, Oct/Oap and NFκB) which are critical for T-cell activation (Lewis,Biochemical Society Transactions (2003), 31:925-929, the entireteachings of which are incorporated herein by reference). Withoutwishing to be bound by any theory, it is believed that because thecompounds of the invention inhibit the activity of CRAC ion channels,they inhibit immune cell activation.

Methods of Treatment and Prevention

In accordance with the invention, an effective amount of a compound ofany one of formulas (I) through (II) or Table 1, or a pharmaceuticallyacceptable salt, solvate, clathrate, and prodrug thereof, or apharmaceutical composition comprising a compound of any one of formulas(I) through (II) or Table 1, or a pharmaceutically acceptable salt,solvate, clathrate, and prodrug thereof, is administered to a patient inneed of immunosuppression or in need of treatment or prevention of aninflammatory condition, an immune disorder, or an allergic disorder.Such patients may be treatment naïve or may experience partial or noresponse to conventional therapies.

Responsiveness of a particular inflammatory condition, immune disorder,or allergic disorder in a subject can be measured directly (e.g.,measuring blood levels of inflammatory cytokines (such as IL-2, IL-4,IL-5, IL-13, GM-CSF, TNF-α, IFN-γ and the like) after administration ofa compound of this invention), or can be inferred based on anunderstanding of disease etiology and progression. The compounds of anyone of formulas (I) through (II), or Table 1, or pharmaceuticallyacceptable salts, solvates, clathrates, and prodrugs thereof can beassayed in vitro or in vivo, for the desired therapeutic or prophylacticactivity, prior to use in humans. For example, known animal models ofinflammatory conditions, immune disorders, or allergic disorders can beused to demonstrate the safety and efficacy of compounds of thisinvention.

Pharmaceutical Compositions and Dosage Forms

Pharmaceutical compositions and dosage forms of the invention compriseone or more active ingredients in relative amounts and formulated insuch a way that a given pharmaceutical composition or dosage form can beused for immunosuppression or to treat or prevent inflammatoryconditions, immune disorders, and allergic disorders. Preferredpharmaceutical compositions and dosage forms comprise a compound of anyone of formulas (I) through (II), or Table 1, or a pharmaceuticallyacceptable prodrug, salt, solvate, or clathrate thereof, optionally incombination with one or more additional active agents.

Single unit dosage forms of the invention are suitable for oral, mucosal(e.g., nasal, sublingual, vaginal, buccal, or rectal), parenteral (e.g.,subcutaneous, intravenous, bolus injection, intramuscular, orintraarterial), or transdermal administration to a patient. Examples ofdosage forms include, but are not limited to: tablets; caplets;capsules, such as soft elastic gelatin capsules; cachets; troches;lozenges; dispersions; suppositories; ointments; cataplasms (poultices);pastes; powders; dressings; creams; plasters; solutions; patches;aerosols (e.g., nasal sprays or inhalers); gels; liquid dosage formssuitable for oral or mucosal administration to a patient, includingsuspensions (e.g., aqueous or non-aqueous liquid suspensions,oil-in-water emulsions, or a water-in-oil liquid emulsions), solutions,and elixirs; liquid dosage forms suitable for parenteral administrationto a patient; and sterile solids (e.g., crystalline or amorphous solids)that can be reconstituted to provide liquid dosage forms suitable forparenteral administration to a patient.

The composition, shape, and type of dosage forms of the invention willtypically vary depending on their use. For example, a dosage formsuitable for mucosal administration may contain a smaller amount ofactive ingredient(s) than an oral dosage form used to treat the sameindication. This aspect of the invention will be readily apparent tothose skilled in the art. See, e.g., Remington's Pharmaceutical Sciences(1990) 18th ed., Mack Publishing, Easton Pa.

Typical pharmaceutical compositions and dosage forms comprise one ormore excipients. Suitable excipients are well known to those skilled inthe art of pharmacy, and non-limiting examples of suitable excipientsare provided herein. Whether a particular excipient is suitable forincorporation into a pharmaceutical composition or dosage form dependson a variety of factors well known in the art including, but not limitedto, the way in which the dosage form will be administered to a patient.For example, oral dosage forms such as tablets may contain excipientsnot suited for use in parenteral dosage forms.

The suitability of a particular excipient may also depend on thespecific active ingredients in the dosage form. For example, thedecomposition of some active ingredients can be accelerated by someexcipients such as lactose, or when exposed to water. Active ingredientsthat comprise primary or secondary amines (e.g., N-desmethylvenlafaxineand N,N-didesmethylvenlafaxine) are particularly susceptible to suchaccelerated decomposition. Consequently, this invention encompassespharmaceutical compositions and dosage forms that contain little, ifany, lactose. As used herein, the term “lactose-free” means that theamount of lactose present, if any, is insufficient to substantiallyincrease the degradation rate of an active ingredient. Lactose-freecompositions of the invention can comprise excipients that are wellknown in the art and are listed, for example, in the U.S. Pharmocopia(USP) SP (XXI)/NF (XVI). In general, lactose-free compositions compriseactive ingredients, a binder/filler, and a lubricant in pharmaceuticallycompatible and pharmaceutically acceptable amounts. Preferredlactose-free dosage forms comprise active ingredients, microcrystallinecellulose, pre-gelatinized starch, and magnesium stearate.

This invention further encompasses anhydrous pharmaceutical compositionsand dosage forms comprising active ingredients, since water canfacilitate the degradation of some compounds. For example, the additionof water (e.g., 5%) is widely accepted in the pharmaceutical arts as ameans of simulating long-term storage in order to determinecharacteristics such as shelf-life or the stability of formulations overtime. See, e.g., Jens T. Carstensen (1995) Drug Stability: Principles &Practice, 2d. Ed., Marcel Dekker, NY, N.Y., 379-80. In effect, water andheat accelerate the decomposition of some compounds. Thus, the effect ofwater on a formulation can be of great significance since moistureand/or humidity are commonly encountered during manufacture, handling,packaging, storage, shipment, and use of formulations.

Anhydrous pharmaceutical compositions and dosage forms of the inventioncan be prepared using anhydrous or low moisture containing ingredientsand low moisture or low humidity conditions. Pharmaceutical compositionsand dosage forms that comprise lactose and at least one activeingredient that comprises a primary or secondary amine are preferablyanhydrous if substantial contact with moisture and/or humidity duringmanufacturing, packaging, and/or storage is expected.

An anhydrous pharmaceutical composition should be prepared and storedsuch that its anhydrous nature is maintained. Accordingly, anhydrouscompositions are preferably packaged using materials known to preventexposure to water such that they can be included in suitable formularykits. Examples of suitable packaging include, but are not limited to,hermetically sealed foils, plastics, unit dose containers (e.g., vials),blister packs, and strip packs.

The invention further encompasses pharmaceutical compositions and dosageforms that comprise one or more compounds that reduce the rate by whichan active ingredient will decompose. Such compounds, which are referredto herein as “stabilizer” include, but are not limited to, antioxidantssuch as ascorbic acid, pH buffers, or salt buffers.

Like the amounts and types of excipients, the amounts and specific typesof active ingredients in a dosage form may differ depending on factorssuch as, but not limited to, the route by which it is to be administeredto patients. However, typical dosage forms of the invention comprise acompound of any one of formulas (I) through (II), or Table 1, or apharmaceutically acceptable salt, solvate, clathrate, or prodrug thereofin an amount of from about 1 mg to about 1000 mg, preferably in anamount of from about 50 mg to about 500 mg, and most preferably in anamount of from about 75 mg to about 350 mg. The typical total dailydosage of a compound of any one of formulas (I) through (II), or Table1, or a pharmaceutically acceptable salt, solvate, clathrate, or prodrugthereof can range from about 1 mg to about 5000 mg per day, preferablyin an amount from about 50 mg to about 1500 mg per day, more preferablyfrom about 75 mg to about 1000 mg per day. It is within the skill of theart to determine the appropriate dose and dosage form for a givenpatient.

Oral Dosage Forms

Pharmaceutical compositions of the invention that are suitable for oraladministration can be presented as discrete dosage forms, such as, butare not limited to, tablets (e.g., chewable tablets), caplets, capsules,and liquids (e.g., flavored syrups). Such dosage forms containpredetermined amounts of active ingredients, and may be prepared bymethods of pharmacy well known to those skilled in the art. Seegenerally, Remington's Pharmaceutical Sciences (1990) 18th ed., MackPublishing, Easton Pa.

Typical oral dosage forms of the invention are prepared by combining theactive ingredient(s) in an admixture with at least one excipientaccording to conventional pharmaceutical compounding techniques.Excipients can take a wide variety of forms depending on the form ofpreparation desired for administration. For example, excipients suitablefor use in oral liquid or aerosol dosage forms include, but are notlimited to, water, glycols, oils, alcohols, flavoring agents,preservatives, and coloring agents. Examples of excipients suitable foruse in solid oral dosage forms (e.g., powders, tablets, capsules, andcaplets) include, but are not limited to, starches, sugars,micro-crystalline cellulose, diluents, granulating agents, lubricants,binders, and disintegrating agents.

Because of their ease of administration, tablets and capsules representthe most advantageous oral dosage unit forms, in which case solidexcipients are employed. If desired, tablets can be coated by standardaqueous or nonaqueous techniques. Such dosage forms can be prepared byany of the methods of pharmacy. In general, pharmaceutical compositionsand dosage forms are prepared by uniformly and intimately admixing theactive ingredients with liquid carriers, finely divided solid carriers,or both, and then shaping the product into the desired presentation ifnecessary.

For example, a tablet can be prepared by compression or molding.Compressed tablets can be prepared by compressing in a suitable machinethe active ingredients in a free-flowing form such as powder orgranules, optionally mixed with an excipient. Molded tablets can be madeby molding in a suitable machine a mixture of the powdered compoundmoistened with an inert liquid diluent.

Examples of excipients that can be used in oral dosage forms of theinvention include, but are not limited to, binders, fillers,disintegrants, and lubricants. Binders suitable for use inpharmaceutical compositions and dosage forms include, but are notlimited to, corn starch, potato starch, or other starches, gelatin,natural and synthetic gums such as acacia, sodium alginate, alginicacid, other alginates, powdered tragacanth, guar gum, cellulose and itsderivatives (e.g., ethyl cellulose, cellulose acetate, carboxymethylcellulose calcium, sodium carboxymethyl cellulose), polyvinylpyrrolidone, methyl cellulose, pre-gelatinized starch, hydroxypropylmethyl cellulose, (e.g., Nos. 2208, 2906, 2910), microcrystallinecellulose, and mixtures thereof.

Suitable forms of microcrystalline cellulose include, but are notlimited to, the materials sold as AVICEL-PH-101, AVICEL-PH-103 AVICELRC-581, AVICEL-PH-105 (available from FMC Corporation, American ViscoseDivision, Avicel Sales, Marcus Hook, Pa.), and mixtures thereof. Onespecific binder is a mixture of microcrystalline cellulose and sodiumcarboxymethyl cellulose sold as AVICEL RC-581. Suitable anhydrous or lowmoisture excipients or additives include AVICEL-PH-103J and Starch 1500LM.

Examples of fillers suitable for use in the pharmaceutical compositionsand dosage forms disclosed herein include, but are not limited to, talc,calcium carbonate (e.g., granules or powder), microcrystallinecellulose, powdered cellulose, dextrates, kaolin, mannitol, silicicacid, sorbitol, starch, pre-gelatinized starch, and mixtures thereof.The binder or filler in pharmaceutical compositions of the invention istypically present in from about 50 to about 99 weight percent of thepharmaceutical composition or dosage form.

Disintegrants are used in the compositions of the invention to providetablets that disintegrate when exposed to an aqueous environment.Tablets that contain too much disintegrant may disintegrate in storage,while those that contain too little may not disintegrate at a desiredrate or under the desired conditions. Thus, a sufficient amount ofdisintegrant that is neither too much nor too little to detrimentallyalter the release of the active ingredients should be used to form solidoral dosage forms of the invention. The amount of disintegrant usedvaries based upon the type of formulation, and is readily discernible tothose of ordinary skill in the art. Typical pharmaceutical compositionscomprise from about 0.5 to about 15 weight percent of disintegrant,preferably from about 1 to about 5 weight percent of disintegrant.

Disintegrants that can be used in pharmaceutical compositions and dosageforms of the invention include, but are not limited to, agar-agar,alginic acid, calcium carbonate, microcrystalline cellulose,croscarmellose sodium, crospovidone, polacrilin potassium, sodium starchglycolate, potato or tapioca starch, other starches, pre-gelatinizedstarch, other starches, clays, other algins, other celluloses, gums, andmixtures thereof.

Lubricants that can be used in pharmaceutical compositions and dosageforms of the invention include, but are not limited to, calciumstearate, magnesium stearate, mineral oil, light mineral oil, glycerin,sorbitol, mannitol, polyethylene glycol, other glycols, stearic acid,sodium lauryl sulfate, talc, hydrogenated vegetable oil (e.g., peanutoil, cottonseed oil, sunflower oil, sesame oil, olive oil, corn oil, andsoybean oil), zinc stearate, ethyl oleate, ethyl laureate, agar, andmixtures thereof. Additional lubricants include, for example, a syloidsilica gel (AEROSIL 200, manufactured by W.R. Grace Co. of Baltimore,Md.), a coagulated aerosol of synthetic silica (marketed by Degussa Co.of Plano, Tex.), CAB-O-SIL (a pyrogenic silicon dioxide product sold byCabot Co. of Boston, Mass.), and mixtures thereof. If used at all,lubricants are typically used in an amount of less than about 1 weightpercent of the pharmaceutical compositions or dosage forms into whichthey are incorporated.

Controlled Release Dosage Forms

Active ingredients of the invention can be administered by controlledrelease means or by delivery devices that are well known to those ofordinary skill in the art. Examples include, but are not limited to,those described in U.S. Pat. Nos. 3,845,770; 3,916,899; 3,536,809;3,598,123; and 4,008,719, 5,674,533, 5,059,595, 5,591,767, 5,120,548,5,073,543, 5,639,476, 5,354,556, and 5,733,566, each of which isincorporated herein by reference. Such dosage forms can be used toprovide slow or controlled-release of one or more active ingredientsusing, for example, hydropropylmethyl cellulose, other polymer matrices,gels, permeable membranes, osmotic systems, multilayer coatings,microparticles, liposomes, microspheres, or a combination thereof toprovide the desired release profile in varying proportions. Suitablecontrolled-release formulations known to those of ordinary skill in theart, including those described herein, can be readily selected for usewith the active ingredients of the invention. The invention thusencompasses single unit dosage forms suitable for oral administrationsuch as, but not limited to, tablets, capsules, gelcaps, and capletsthat are adapted for controlled-release.

All controlled-release pharmaceutical products have a common goal ofimproving drug therapy over that achieved by their non-controlledcounterparts. Ideally, the use of an optimally designedcontrolled-release preparation in medical treatment is characterized bya minimum of drug substance being employed to cure or control thecondition in a minimum amount of time. Advantages of controlled-releaseformulations include extended activity of the drug, reduced dosagefrequency, and increased patient compliance. In addition,controlled-release formulations can be used to affect the time of onsetof action or other characteristics, such as blood levels of the drug,and can thus affect the occurrence of side (e.g., adverse) effects.

Most controlled-release formulations are designed to initially releasean amount of drug (active ingredient) that promptly produces the desiredtherapeutic effect, and gradually and continually release of otheramounts of drug to maintain this level of therapeutic or prophylacticeffect over an extended period of time. In order to maintain thisconstant level of drug in the body, the drug must be released from thedosage form at a rate that will replace the amount of drug beingmetabolized and excreted from the body. Controlled-release of an activeingredient can be stimulated by various conditions including, but notlimited to, pH, temperature, enzymes, water, or other physiologicalconditions or compounds.

A particular extended release formulation of this invention comprises atherapeutically or prophylactically effective amount of a compound offormula (I) through (II), or Table 1, or a pharmaceutically acceptablesalt, solvate, hydrate, clathrate, or prodrug thereof, in spheroidswhich further comprise microcrystalline cellulose and, optionally,hydroxypropylmethyl-cellulose coated with a mixture of ethyl celluloseand hydroxypropylmethylcellulose. Such extended release formulations canbe prepared according to U.S. Pat. No. 6,274,171, the entire teachingsof which are incorporated herein by reference.

A specific controlled-release formulation of this invention comprisesfrom about 6% to about 40% a compound of any one of formulas (I) through(II), or Table 1 by weight, about 50% to about 94% microcrystallinecellulose, NF, by weight, and optionally from about 0.25% to about 1% byweight of hydroxypropyl-methylcellulose, USP, wherein the spheroids arecoated with a film coating composition comprised of ethyl cellulose andhydroxypropylmethylcellulose.

Parenteral Dosage Forms

Parenteral dosage forms can be administered to patients by variousroutes including, but not limited to, subcutaneous, intravenous(including bolus injection), intramuscular, and intraarterial. Becausetheir administration typically bypasses patients' natural defensesagainst contaminants, parenteral dosage forms are preferably sterile orcapable of being sterilized prior to administration to a patient.Examples of parenteral dosage forms include, but are not limited to,solutions ready for injection, dry products ready to be dissolved orsuspended in a pharmaceutically acceptable vehicle for injection,suspensions ready for injection, and emulsions.

Suitable vehicles that can be used to provide parenteral dosage forms ofthe invention are well known to those skilled in the art. Examplesinclude, but are not limited to: Water for Injection USP; aqueousvehicles such as, but not limited to, Sodium Chloride Injection,Ringer's Injection, Dextrose Injection, Dextrose and Sodium ChlorideInjection, and Lactated Ringer's Injection; water-miscible vehicles suchas, but not limited to, ethyl alcohol, polyethylene glycol, andpolypropylene glycol; and non-aqueous vehicles such as, but not limitedto, corn oil, cottonseed oil, peanut oil, sesame oil, ethyl oleate,isopropyl myristate, and benzyl benzoate.

Compounds that increase the solubility of one or more of the activeingredients disclosed herein can also be incorporated into theparenteral dosage forms of the invention.

Transdermal, Topical, and Mucosal Dosage Forms

Transdermal, topical, and mucosal dosage forms of the invention include,but are not limited to, ophthalmic solutions, sprays, aerosols, creams,lotions, ointments, gels, solutions, emulsions, suspensions, or otherforms known to one of skill in the art. See, e.g., Remington'sPharmaceutical Sciences (1980 & 1990) 16th and 18th eds., MackPublishing, Easton Pa. and Introduction to Pharmaceutical Dosage Forms(1985) 4th ed., Lea & Febiger, Philadelphia. Dosage forms suitable fortreating mucosal tissues within the oral cavity can be formulated asmouthwashes or as oral gels. Further, transdermal dosage forms include“reservoir type” or “matrix type” patches, which can be applied to theskin and worn for a specific period of time to permit the penetration ofa desired amount of active ingredients.

Suitable excipients (e.g., carriers and diluents) and other materialsthat can be used to provide transdermal, topical, and mucosal dosageforms encompassed by this invention are well known to those skilled inthe pharmaceutical arts, and depend on the particular tissue to which agiven pharmaceutical composition or dosage form will be applied. Withthat fact in mind, typical excipients include, but are not limited to,water, acetone, ethanol, ethylene glycol, propylene glycol,butane-1,3-diol, isopropyl myristate, isopropyl palmitate, mineral oil,and mixtures thereof to form lotions, tinctures, creams, emulsions, gelsor ointments, which are non-toxic and pharmaceutically acceptable.Moisturizers or humectants can also be added to pharmaceuticalcompositions and dosage forms if desired. Examples of such additionalingredients are well known in the art. See, e.g., Remington'sPharmaceutical Sciences (1980 & 1990) 16th and 18th eds., MackPublishing, Easton Pa.

Depending on the specific tissue to be treated, additional componentsmay be used prior to, in conjunction with, or subsequent to treatmentwith active ingredients of the invention. For example, penetrationenhancers can be used to assist in delivering the active ingredients tothe tissue. Suitable penetration enhancers include, but are not limitedto: acetone; various alcohols such as ethanol, oleyl, andtetrahydrofuryl; alkyl sulfoxides such as dimethyl sulfoxide; dimethylacetamide; dimethyl formamide; polyethylene glycol; pyrrolidones such aspolyvinylpyrrolidone; Kollidon grades (Povidone, Polyvidone); urea; andvarious water-soluble or insoluble sugar esters such as Tween 80(polysorbate 80) and Span 60 (sorbitan monostearate).

The pH of a pharmaceutical composition or dosage form, or of the tissueto which the pharmaceutical composition or dosage form is applied, mayalso be adjusted to improve delivery of one or more active ingredients.Similarly, the polarity of a solvent carrier, its ionic strength, ortonicity can be adjusted to improve delivery. Compounds such asstearates can also be added to pharmaceutical compositions or dosageforms to advantageously alter the hydrophilicity or lipophilicity of oneor more active ingredients so as to improve delivery. In this regard,stearates can serve as a lipid vehicle for the formulation, as anemulsifying agent or surfactant, and as a delivery-enhancing orpenetration-enhancing agent. Different salts, hydrates or solvates ofthe active ingredients can be used to further adjust the properties ofthe resulting composition.

Combination Therapy

The methods for immunosuppression or for treating or preventinginflammatory conditions and immune disorders in a patient in needthereof can further comprise administering to the patient beingadministered a compound of this invention, an effective amount of one ormore other active agents. Such active agents may include those usedconventionally for immunosuppression or for inflammatory conditions orimmune disorders. These other active agents may also be those thatprovide other benefits when administered in combination with thecompounds of this invention. For example, other therapeutic agents mayinclude, without limitation, steroids, non-steroidal anti-inflammatoryagents, antihistamines, analgesics, immunosuppressive agents andsuitable mixtures thereof. In such combination therapy treatment, boththe compounds of this invention and the other drug agent(s) areadministered to a subject (e.g., humans, male or female) by conventionalmethods. The agents may be administered in a single dosage form or inseparate dosage forms. Effective amounts of the other therapeutic agentsand dosage forms are well known to those skilled in the art. It is wellwithin the skilled artisan's purview to determine the other therapeuticagent's optimal effective-amount range.

In one embodiment of the invention where another therapeutic agent isadministered to a subject, the effective amount of the compound of thisinvention is less than its effective amount when the other therapeuticagent is not administered. In another embodiment, the effective amountof the conventional agent is less than its effective amount when thecompound of this invention is not administered. In this way, undesiredside effects associated with high doses of either agent may beminimized. Other potential advantages (including without limitationimproved dosing regimens and/or reduced drug cost) will be apparent tothose of skill in the art.

In one embodiment relating to autoimmune and inflammatory conditions,the other therapeutic agent may be a steroid or a non-steroidalanti-inflammatory agent. Particularly useful non-steroidalanti-inflammatory agents, include, but are not limited to, aspirin,ibuprofen, diclofenac, naproxen, benoxaprofen, flurbiprofen, fenoprofen,flubufen, ketoprofen, indoprofen, piroprofen, carprofen, oxaprozin,pramoprofen, muroprofen, trioxaprofen, suprofen, aminoprofen,tiaprofenic acid, fluprofen, bucloxic acid, indomethacin, sulindac,tolmetin, zomepirac, tiopinac, zidometacin, acemetacin, fentiazac,clidanac, oxpinac, mefenamic acid, meclofenamic acid, flufenamic acid,niflumic acid, tolfenamic acid, diflurisal, flufenisal, piroxicam,sudoxicam, isoxicam; salicylic acid derivatives, including aspirin,sodium salicylate, choline magnesium trisalicylate, salsalate,diflunisal, salicylsalicylic acid, sulfasalazine, and olsalazin;para-aminophennol derivatives including acetaminophen and phenacetin;indole and indene acetic acids, including indomethacin, sulindac, andetodolac; heteroaryl acetic acids, including tolmetin, diclofenac, andketorolac; anthranilic acids (fenamates), including mefenamic acid, andmeclofenamic acid; enolic acids, including oxicams (piroxicam,tenoxicam), and pyrazolidinediones (phenylbutazone, oxyphenthartazone);and alkanones, including nabumetone and pharmaceutically acceptablesalts thereof and mixtures thereof. For a more detailed description ofthe NSAIDs, see Paul A. Insel, Analgesic-Antipyretic andAntiinflammatory Agents and Drugs Employed in the Treatment of Gout, inGoodman & Gilman's The Pharmacological Basis of Therapeutics 617-57(Perry B. Molinhoff and Raymond W. Ruddon eds., 9^(th) ed 1996) and GlenR. Hanson, Analgesic, Antipyretic and Anti-Inflammatory Drugs inRemington: The Science and Practice of Pharmacy Vol II 1196-1221 (A. R.Gennaro ed. 19th ed. 1995) which are hereby incorporated by reference intheir entireties.

Of particular relevance to allergic disorders, the other therapeuticagent may be an antihistamine. Useful antihistamines include, but arenot limited to, loratadine, cetirizine, fexofenadine, desloratadine,diphenhydramine, chlorpheniramine, chlorcyclizine, pyrilamine,promethazine, terfenadine, doxepin, carbinoxamine, clemastine,tripelennamine, brompheniramine, hydroxyzine, cyclizine, meclizine,cyproheptadine, phenindamine, acrivastine, azelastine, levocabastine,and mixtures thereof. For a more detailed description ofanthihistamines, see Goodman & Gilman's The Pharmacological Basis ofTherapeutics (2001) 651-57, 10^(th) ed).

Immunosuppressive agents include glucocorticoids, corticosteroids (suchas Prednisone or Solumedrol), T cell blockers (such as cyclosporin A andFK506), purine analogs (such as azathioprine (Imuran)), pyrimidineanalogs (such as cytosine arabinoside), alkylating agents (such asnitrogen mustard, phenylalanine mustard, buslfan, and cyclophosphamide),folic acid antagonists (such as aminopterin and methotrexate),antibiotics (such as rapamycin, actinomycin D, mitomycin C, puramycin,and chloramphenicol), human IgG, antilymphocyte globulin (ALG), andantibodies (such as anti-CD3 (OKT3), anti-CD4 (OKT4), anti-CD5,anti-CD7, anti-IL-2 receptor, anti-alpha/beta TCR, anti-ICAM-1,anti-CD20 (Rituxan), anti-IL-12 and antibodies to immunotoxins).

The foregoing and other useful combination therapies will be understoodand appreciated by those of skill in the art. Potential advantages ofsuch combination therapies include a different efficacy profile, theability to use less of each of the individual active ingredients tominimize toxic side effects, synergistic improvements in efficacy,improved ease of administration or use and/or reduced overall expense ofcompound preparation or formulation.

Other Embodiments

The compounds of this invention may be used as research tools (forexample, as a positive control for evaluating other potential CRACinhibitors, or IL-2, IL-4, IL-5, IL-13, GM-CSF, TNF-α, and/or INF-γinhibitors). These and other uses and embodiments of the compounds andcompositions of this invention will be apparent to those of ordinaryskill in the art.

The invention is further defined by reference to the following examplesdescribing in detail the preparation of compounds of the invention. Itwill be apparent to those skilled in the art that many modifications,both to materials and methods, may be practiced without departing fromthe purpose and interest of this invention. The following examples areset forth to assist in understanding the invention and should not beconstrued as specifically limiting the invention described and claimedherein. Such variations of the invention, including the substitution ofall equivalents now known or later developed, which would be within thepurview of those skilled in the art, and changes in formulation or minorchanges in experimental design, are to be considered to fall within thescope of the invention incorporated herein.

EXAMPLES Experimental Rationale

Without wishing to be bound by theory, it is believed that the compoundsof this invention inhibit CRAC ion channels, thereby inhibitingproduction of IL-2 and other key cytokines involved with inflammatoryand immune responses. The examples that follow demonstrate theseproperties.

Materials and General Methods

Reagents and solvents used below can be obtained from commercial sourcessuch as Aldrich Chemical Co. (Milwaukee, Wis., USA). ¹H-NMR and ¹³C-NMRspectra were recorded on a Varian 300 MHz NMR spectrometer. Significantpeaks are tabulated in the order: δ (ppm): chemical shift, multiplicity(s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; br s,broad singlet), coupling constant(s) in Hertz (Hz) and number ofprotons.

Patch clamp experiments were performed in the tight-seal whole-cellconfiguration at 21-25° C. High resolution current recordings wereacquired by a computer-based patch clamp amplifier system (EPC-9, HEKA,Lambrecht, Germany). Patch pipettes had resistances between 2-4 MO afterfilling with the standard intracellular solution. Immediately followingestablishment of the whole-cell configuration, voltage ramps of 50-200ms duration spanning the voltage range of −100 to +100 mV were deliveredat a rate of 0.5 Hz over a period of 300-400 seconds. All voltages werecorrected for a liquid junction potential of 10 mV between external andinternal solutions when using glutamate as the intracellular anion.Currents were filtered at 2.9 kHz and digitized at 10 μs intervals.Capacitive currents and series resistance were determined and correctedbefore each voltage ramp using the automatic capacitance compensation ofthe EPC-9. The low resolution temporal development of membrane currentswas assessed by extracting the current amplitude at −80 mV or +80 mVfrom individual ramp current records.

Compounds of the invention can also be prepared as in U.S. applicationSer. No. 10/897,681, filed Jul. 22, 2004 and U.S. application Ser. No.11/326,872 entitled “Compounds for Inflammation and Immune-RelatedUses,” by Lijun Sun, et al., filed on Jan. 6, 2006, the entire teachingsof which are incorporated herein by reference.

Example 1 Synthesis of Representative Exemplary Compounds of thisInvention Compound 1:N-[6-(2-chloro-5-trifluoromethyl-phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide

A mixture of 2-chloro-5-trifluoromethyl-phenylboronic acid (a, 1 mmol),6-bromo-pyridin-3-ylamine (b, 1 mmol), palladium catalyst (0.1 mmol),sodium bicarbonate (1 mmol) in a mixture of toluene (5 mL), water (1mL), ethanol (1 mL) was heated at 100° C. for 24 h. The mixture wastaken up with EtOAc (100 mL), washed with water (2×100 mL) and dried(Na₂SO₄). The oil obtained on concentration was purified by flashchromatography to give c as a yellowish oil (0.20 mg).

The above oil was treated with 2,6-difluorobenzoic chloride (0.6 mmol)in DCM (5 mL) and pyridine (0.2 mL) at rt for 2 h. Removal of solventsand purification of the residue by chromatography gave product d asyellow solid (0.15 g). ¹H-NMR (CDCl₃) δ 8.8 (d, 1H, J=2), 8.5 (dd, 1H,J₁=9, J₂=2), 7.91 (s, 2H), 7.8 (d, 1H, J=8), 7.6 (m, 2H), 7.5 (m, 1H),7.0 (t, 2H, J=8) ppm; ESMS calcd for C₁₉H₁₀ClF₅N₂O: 412.0; found: 413.0(M+H⁺).

Compound 2 through Compound 22 were synthesized in a similar manner:

Compound 2:N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide

¹H-NMR (CDCl₃) δ 9.2 (m, 1H), 8.5 (m, 1H), 8.18 (s, 1H), 7.9 (m, 1H),7.6 (m, 3H), 7.4 (m, 1H), 7.0 (t, 2H, J=8) ppm; ESMS calcd forC₁₉H₁₀ClF₅N₂O: 412.0; found: 413.0 (M+H⁺).

Compound 3:N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide

¹H-NMR (CDCl₃) δ 9.20 (s, 1H), 8.6 (m, 2H), 8.5 (d, 1H, J=9), 8.11 (s,1H), 7.9 (d, 1H, J=9), 7.6 (m, 3H), 7.4 (d, 1H, J=5), 2.52 (s, 3H) ppm;ESMS calcd for C₁₉H₁₃ClF₃N₃O: 391.1; found: 392.0 (M+H⁺).

Compound 4:N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-3-fluoro-isonicotinamide

¹H-NMR (CDCl₃) δ 9.2 (br, 1H), 8.7 (m, 2H), 8.4 (m, 2H), 8.0 (t, 1H,J=6), 7.9 (dd, 1H, J₁=9, J₂=2), 7.6 (m, 3H) ppm; ESMS calcd forC₁₈H₁₀ClF₄N₃O: 395.0; found: 396.0 (M+H⁺).

Compound 5:2,6-Difluoro-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide

¹H-NMR (CDCl₃) δ 8.6 (br, 1H), 8.4 (d, 1H, J=8), 8.26 (s, 1H), 8.0 (d,1H, J=8), 7.91 (s, 1H), 7.8 (d, 1H, J=8), 7.71 (s, 1H), 7.4 (m, 2H), 7.3(m, 1H), 7.0 (m, 2H), 2.33 (s, 3H) ppm; ESMS calcd for C₂₀H₁₅F₂N₃O₂:391.1; found: 392.1 (M+H⁺).

Compound 6:4-Chloro-3-[6-(2,6-difluoro-benzoylamino)-pyridin-3-yl]-benzoic acidmethyl ester

¹H-NMR (CDCl₃) δ 8.7 (br, 1H), 8.5 (d, 1H, J=8), 8.3 (m, 1H), 8.0 (m,2H), 7.9 (d, 1H, J=8), 7.6 (d, 1H, J=9), 7.4 (m, 1H), 7.0 (t, 2H, J=8),3.94 (s, 3H) ppm; ESMS calcd for C₂₀H₁₃ClF₂N₂O₃: 402.1; found: 403.0(M+H⁺).

Compound 7:3-[6-(2,6-Difluoro-benzoylamino)-pyridin-3-yl]-4-methyl-benzoic acidmethyl ester

¹H-NMR (CDCl₃) δ 9.5 (br, 1H), 8.4 (d, 1H, J=8), 8.0 (m, 2H), 7.9 (m,2H), 7.4 (m, 2H), 7.0 (t, 2H, J=8), 3.94 (s, 3H), 2.30 (s, 3H) ppm; ESMScalcd for C₂₁H₁₆F₂N₂O₃: 382.1; found: 383.1 (M+H⁺).

Compound 8:N-[5-(2-Chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide

¹H-NMR (CDCl₃) δ 9.8 (br, 1H), 8.5 (m, 1H), 8.0 (m, 4H), 7.8 (m, 1H),7.6 (m, 1H), 7.4 (m, 2H), 7.0 (m, 2H) ppm; ESMS calcd forC₂₁H₁₂ClF₂N₃O₂: 411.1; found: 412.0 (M+H⁺).

Compound 9:N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-6-methyl-pyridin-2-yl]-2,6-difluoro-benzamide

¹H-NMR (CDCl₃) δ 9.1 (br, 1H), 8.3 (d, 1H, J=8), 7.3-7.6 (m, 5H), 7.0(t, 2H, J=8), 2.16 (s, 3H) ppm; ESMS calcd for C₂₀H₁₂ClF₅N₂O: 426.1;found: 427.0 (M+H⁺).

Compound 10:N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide

¹H-NMR (CDCl₃) δ 9.6 (br, 1H), 8.5 (d, 1H, J=8), 8.07 (s, 1H), 7.9 (m,4H), 7.6 (d, 1H, J=9), 7.4 (m, 2H), 7.0 (t, 2H, J=8) ppm; ESMS calcd forC₂₀H₁₂ClF₂N₃OS: 427.0; found: 428.0 (M+H⁺).

Compound 11:N-[5-(2-Chloro-5-trifluoromethyl-phenyl)-4-methyl-pyridin-2-yl]-2,6-difluoro-benzamide

¹H-NMR (CDCl₃) δ 10.6 (br, 1H), 8.40 (s, 1H), 7.6 (m, 2H), 7.4 (m, 3H),6.9 (m, 2H), 2.21 (s, 3H) ppm; ESMS calcd for C₂₀H₁₂ClF₅N₂O: 426.1;found: 427.0 (M+H⁺).

Compound 12:3-[5-(2,6-Difluoro-benzoylamino)-pyridin-2-yl]-4-methyl-benzoic acidmethyl ester

¹H-NMR (CDCl₃) δ 8.72 (s, 1H), 8.4 (d, 1H, J=8), 8.09 (s, 1H), 8.0 (d,1H, J=8), 7.8 (br, 1H), 7.5 (m, 2H), 7.4 (d, 1H, J=8), 7.0 (t, 2H, J=8),3.91 (s, 3H), 2.45 (s, 3H) ppm; ESMS calcd for C₂₁H₁₆F₂N₂O₃: 382.1;found: 383.1 (M+H⁺).

Compound 13:2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide

¹H-NMR (CDCl₃) δ 8.72 (s, 1H), 8.4 (d, 1H, J=8), 8.32 (s, 1H), 8.04 (s,1H), 8.0 (d, 1H, J=8), 7.64 (s, 1H), 7.4 (m, 3H), 7.20 (s, 1H), 7.0 (t,2H, J=8), 2.38 (s, 3H) ppm; ESMS calcd for C₂₂H₁₅F₂N₃O₂: 391.1; found:392.1 (M+H⁺).

Compound 14:2,6-Difluoro-N-[4-methyl-5-(3-trifluoromethyl-phenyl)-pyridin-2-yl]-benzamide

¹H-NMR (CDCl₃) δ 9.4 (br, 1H), 8.37 (s, 1H), 7.80 (s, 1H), 7.3-7.7 (m,5H), 7.0 (t, 2H, J=8), 2.34 (s, 3H) ppm; ESMS calcd for C₂₀H₁₃F₅N₂O:392.1; found: 393.0 (M+H⁺).

Compound 15:2,6-Difluoro-N-[6-methyl-5-(3-trifluoromethyl-phenyl)-pyridin-2-yl]-benzamide

¹H-NMR (CDCl₃) δ 8.9 (br, 1H), 8.3 (d, 1H, J=8), 7.3-7.7 (m, 6H), 7.0(t, 2H, J=8), 2.32 (s, 3H) ppm; ESMS calcd for C₂₀H₁₃F₅N₂O: 392.1;found: 393.0 (M+H⁺).

Compound 16: 4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-trifluoromethyl-phenyl)-pyridin-2-yl]-amide

¹H-NMR (CDCl₃) δ 9.1 (br, 1H), 8.4 (d, 1H, J=9), 8.29 (s, 1H), 8.0 (d,1H, J=8), 7.6 (m, 3H), 3.02 (s, 3H) ppm; ESMS calcd for C₁₆H₁₀ClF₃N₄OS:398.0; found: 399.0 (M+H⁺).

Compound 17: 4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-amide

¹H-NMR (CDCl₃) δ 8.4 (m, 3H), 7.9 (m, 4H), 7.6 (d, 1H, J=8), 7.4 (d, 1H,J=5), 3.05 (s, 3H) ppm; ESMS calcd for C₁₈H₁₂ClN₅OS₂: 413.0; found:414.0 (M+H⁺).

Compound 18: 4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide

¹H-NMR (CDCl₃) δ 9.4 (br, 1H), 8.4 (d, 1H, J=8), 8.31 (s, 1H), 7.9 (m,3H), 7.72 (s, 1H), 7.4 (d, 1H, J=8), 7.24 (s, 1H), 3.03 (s, 3H), 2.34(s, 3H) ppm; ESMS calcd for C₁₉H₁₅N₅O₂S: 377.1; found: 378.1 (M+H⁺).

Compound 19: 4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide

¹H-NMR (CDCl₃) δ 8.6 (d, 1H, J=9), 8.42 (s, 1H), 8.1 (m, 3H), 7.77 (s,1H), 7.6 (s, 1H, J=8), 7.30 (s, 1H), 3.03 (s, 3H) ppm; ESMS calcd forC₁₈H₁₂ClN₅O₂S: 397.0; found: 398.1 (M+H⁺).

Compound 20:2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride

¹H-NMR (DMSO-d₆) δ 11.6 (br, 1H), 9.12 (s, 1H), 8.4 (d, 1H, J=8), 8.12(s, 1H), 8.0 (m, 2H), 7.9 (d, 1H, J=8), 7.6 (m, 1H), 7.5 (d, 1H, J=8),7.41 (s, 1H), 7.3 (t, 2H, J=8), 2.41 (s, 3H) ppm; ESMS calcd forC₂₂H₁₆ClF₂N₃O₂: 427.1; found: 398.1 (M+H⁺).

Compound 21:4-methyl-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-1,2,3-thiadiazole-5-carboxamide

¹H NMR (300 MHz, (CD₃)₂SO) 11.55 (s, 1H), 8.45-8.43 (m, 2H), 8.22-8.19(m, 1H), 7.98-7.94 (m, 1H), 7.71-7.63 (m, 3H), 7.46-7.43 (m, 1H), 2.82(s, 3H), 2.28 (s, 3H); ESMS calcd (C₁₉H₁₅N₅O₂S): 377.1; found: 378.2(M+H).

Compound 68:N-(5-(5-(isoxazol-5-yl)-2-methylphenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamide

General Procedure for Suzuki Cross Coupling:

To a solution of 5-(3-bromo-4-methylphenyl)isoxazole (200 mg, 0.84mmol), dichlorobis(triphenylphosphine)palladium (II) (Pd(PPh₃)₂Cl₂, 60mg, 0.09 mmol), and 6-aminopyridin-3-ylboronic acid pinacol ester (185mg, 0.84 mmol) in toluene (10 mL) was added Na₂CO₃ (2 N, 1.0 mL) andethanol (1.0 mL). The stirred mixture was heated up to 80° C. for 16 hr.The solution was cooled to room temperature and diluted with H₂O (10 mL)and EtOAc (10 mL). The organic phase was dried over Na₂SO₄,concentrated, and chromatographied to give the pure product (120 mg,57%).

General Procedure a for Amide Bond Formation:

To a solution of 5-(5-(isoxazol-5-yl)-2-methylphenyl)pyridin-2-amine (60mg, 0.24 mmol) in DCM (4 mL) was added EDC (85 mg, 0.45 mmol) and4-methyl-1,2,3-thiadiazole-5-carboxylic acid (70 mg, 0.48 mmol). Thesolution was stirred at room temperature for 6 hr before it wasconcentrated and chromatographied to give the pure product (50 mg, 55%).

¹H NMR (300 MHz, CDCl₃) δ 8.58 (d, J=9 Hz, 1H), 8.32-8.28 (m, 2H),7.99-7.95 (m, 1H), 7.78-714 (m, 1H), 7.68 (d, J=1.8 Hz, 1H), 7.45-7.43(m, 1H), 6.54 (d, J=1.8 Hz, 1H), 2.35 (d, 3H);). ESMS calcd(C₁₉H₁₅N₅O₂S): 377.1; found: 378.1 (M+H).

Compound 69:2,6-difluoro-N-(5-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)benzamide

General Procedure B for Amide Bond Formation:

To the solution of5-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-amine (100 mg, 0.4mmol) in 3 DCM (3 mL) was added 2,6-difluorobenzoyl chloride (0.1 mL,0.8 mmol). The reaction solution was stirred at room temperature for 60min before it was concentrated and chromatographied to afford themixture of mono amide and di-amide products. The mixture was dissolvedin 5 mL MeOH and heated at 50° C. for 25 min before it was concentratedand extracted between ethyl acetate and H₂O. The organic phase was driedand concentrated to afford the pure final product (117 mg, 75%).

¹H NMR (300 MHz, CDCl₃) δ 9.16 (s, 1H), 8.51-8.48 (m, 2H), 8.14-8.12 (m,1H), 8.01 (dd, J=8.1 and 2.1 Hz, 1H), 7.91 (d, J=1.8 Hz, 1H), 7.79 (dd,J=8.7 and 2.4 Hz, 1H), 7.45-7.42 (m, 2H), 7.05-6.98 (m, 2H), 2.35 (s,3H); ESMS calcd (C₂₁H₁₄F₂N₄O₂): 392.1; found: 393.2 (M+H).

Compound 70:2,6-difluoro-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)benzamide

¹H NMR (300 MHz, CDCl₃) δ 8.81 (s, 1H), 8.47 (d, J=8.4 Hz, 1H),8.21-8.20 (m, 1H), 7.92 (s, 1H), 7.78 (dd, J=8.4 and 2.1 Hz, 1H), 7.59(dd, J=7.8 and 1.8 Hz, 1H), 7.50-7.35 (m, 4H), 7.05-6.99 (m, 2H), 2.30(s, 3H); ESMS calcd (C₂₂H₁₅F₂N₃O₂): 391.1; found: 392.2 (M+H).

Compound 71:N-(5-(2-chloro-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)-2,6-difluorobenzamide

¹H NMR (300 MHz, CDCl₃) δ 9.07 (s, 1H), 8.52-8.49 (m, 2H), 8.26 (d,J=1.8 Hz, 1H), 8.07-8.03 (m, 2H), 7.93 (dd, J=8.7 and 2.4 Hz, 1H),7.69-7.66 (m, 1H), 7.48-7.42 (m, 1H), 7.05-6.98 (m, 2H); ESMS calcd(C₂₀H₁₁ClF₂N₄O₂): 412.1; found: 413.2 (M+H).

Compound 72:N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide

¹H NMR (300 MHz, CDCl₃) δ 8.76 (d, J=2.7 Hz, 1H), 8.42 (dd, J=8.7 and2.7 Hz, 1H), 8.34 (s, 1H), 8.14 (d, J=2.4 Hz, 1H), 7.92 (dd, J=8.6 and2.3 Hz, 1H), 7.85 (d, J=3.3 Hz, 1H), 7.73 (d, J=8.7 Hz, 1H), 7.55 (d,J=8.4 Hz, 1H), 7.45-7.35 (m, 2H), 7.02-6.95 (m, 2H); ESMS calcd(C₂H₁₂ClF₂N₃OS): 427.0; found: 428.1 (M+H).

Compound 73:N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt

¹H NMR (300 MHz, CD₃OD) δ 9.62 (d, J=2.1 Hz, 1H), 8.72-8.67 (m, 1H),8.36-8.23 (m, 3H), 8.00 (d, J=3.3 Hz, 1H), 7.86 (d, J=8.1 Hz, 1H), 7.79(d, J=3.3 Hz, 1H), 7.66-7.61 (m, 1H), 7.19 (t, J=8.1 Hz, 2H); ESMS calcd(C₂₁H₁₂ClF₂N₃OS): 427.0; found: 428.1 (M+H).

Compound 74:2,6-Difluoro-N-(6-(2-methyl-5-(thiazol-2-yl)phenyl)pyridin-3-yl)benzamide

¹H NMR (300 MHz, CDCl₃) δ 8.74 (d, J=2.4 Hz, 1H), 8.43 (dd, J=8.6 and2.6 Hz, 1H), 8.02-7.98 (m, 2H), 7.89 (dd, J=5.0 and 2.1 Hz, 1H), 7.84(d, J=3.3 Hz, 1H), 7.53-7.30 (m, 4H), 7.03 (t, J=8.3 Hz, 2H); ESMS calcd(C₂₂H₁₅F₂N₃₀S): 407.1; found: 408.2 (M+H).

Compound 75:2,6-Difluoro-N-(6-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-3-yl)benzamide

¹H NMR (300 MHz, CDCl₃) δ 8.76 (d, J=2.4 Hz, 1H), 8.45-8.41 (m, 2H),8.29 (s, 1H), 8.10 (d, J=1.8 Hz, 1H), 8.00 (dd, J=8.0 and 2.0 Hz, 1H),7.51-7.42 (m, 3H), 7.01 (t, J=8.1 Hz, 2H), 2.45 (s, 3H); ESMS calcd(C₂₁H₁₄F₂N₄O₂): 392.1; found: 393.2 (M+H).

Compound 76:N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide

¹H NMR (300 MHz, CD₃OD) δ 8.96-8.94 (m, 1H), 8.37 (dd, J=8.6 and 2.6 Hz,1H), 8.22 (d, J=2.1 Hz, 1H), 8.08-8.04 (m, 1H), 8.02 (d, J=0.9 Hz, 1H),7.80-7.76 (m, 1H), 7.70 (d, J=8.4 Hz, 1H), 7.60-7.54 (m, 1H), 7.33 (d,J=0.9 Hz, 1H), 7.17-7.12 (m, 2H); ESMS calcd (C₂₁H₁₂ClF₂N₃O₂): 411.1;found: 412.2 (M+H).

Compound 77:N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt

¹H NMR (300 MHz, CD₃OD) δ 9.63-9.61 (m, 1H), 8.74-8.68 (m, 1H),8.39-8.27 (m, 3H), 8.10 (d, J=0.6 Hz, 1H), 7.89 (d, J=8.7 Hz, 1H),8.67-8.59 (m, 1H), 7.40 (d, J=0.6 Hz, 1H), 7.19 (t, J=8.1 Hz, 2H); ESMScalcd (C₂₁H₁₂ClF₂N₃O₂): 411.1; found: 412.2 (M+H).

Compound 78:2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamide

¹H NMR (300 MHz, CD₃OD) δ 8.91-8.90 (m, 1H), 8.35 (d, J=8.6 and 2.4 Hz,1H), 8.24 (s, 1H), 7.75-7.67 (m, 2H), 7.61-7.52 (m, 3H), 7.42 (d, J=8.1Hz, 1H), 7.14 (t, J=8.1 Hz, 2H), 2.36 (s, 3H); ESMS calcd(C₂₂H₁₅F₂N₃O₂): 391.1; found: 392.3 (M+H).

Compound 79:2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamidehydrochloric acid salt

¹H NMR (300 MHz, CD₃OD) δ 9.60 (s, 1H), 8.69 (d, J=7.8 Hz, 1H), 8.57 (s,1H), 8.23 (d, J=8.4 Hz, 1H), 7.98-7.92 (m, 2H), 7.76 (s, 1H), 7.66-7.60(m, 2H), 7.19 (t, J=8.1 Hz, 2H), 2.43 (s, 3H); ESMS calcd(C₂₂H₁₅F₂N₃O₂): 391.1; found: 392.3 (M+H).

Compound 80: 4-chloro-2-fluoro-N-(6-(2-methyl-5-(oxazol-2-yl)phenyl)pyridin-3-yl)benzamide

¹H-NMR (CDCl₃) δ (ppm) 8.8 (d, 1H, J=2), 8.5 (br, 1H), 8.4 (dd, 1H,J₁=8, J₂=2), 7.9-8.2 (m, 3H), 7.70 (s, 1H), 7.2-7.5 (m, 5H), 2.42 (s,3H); ESMS clcd for C₂₂H₁₅ClFN₃O₂: 407.1; Found: 408.0 (M+H)⁺.

Compounds of the invention in which L is —NHC(S)— or —C(S)NH— can beprepared by treating compounds having an amide linker with Lawesson'sreagent.

Compounds having —CH₂—NH— or —NH—CH₂— linkers can be prepared bycontacting compounds having —NHC(S)— or —C(S)NH— linkers with Raney Ni.Alternatively, compounds of the invention having a —CH₂—NH— or —NH—CH₂—linker can be prepared by reducing a compound having a —C(O)—NH— or—NH—C(O)— linker, respectively, with, for example, sodium borohydride(see U.S. patent application Ser. No. 10/897,681, filed on Jul. 22,2004, the entire teachings of which are incorporated herein byreference).

Compounds of the invention having —C(O)— linkers can be prepared by aFriedel-Craft acylation reaction, for example, by reacting a pyradinylderivative (XXIII) with an acid chloride (XXIV) in the presence of AlCl₃to form an intermediate which can then be reacted with an[1,3,2]dioxaborolan-2-yl-aryl or -heteroaryl (XXV) in the presence of apalladium catalyst and a base to form a compound of the invention havinga carbonyl linker (XXVI) (see Scheme IV).

Compounds of the invention that have —C(S)— can be prepared fromcompounds that have carbonyl linkers by treating them with Lawesson'sreagent or P₂S₅ in pyridine.

Compounds of the invention having —CH₂—NH— or —NH—CH₂— linkers can beprepared by contacting compounds having —NHC(S)— or —C(S)NH— linkerswith Raney Ni. Alternatively, compounds of the invention having a—CH₂—NH— or —NH—CH₂— linker can be prepared by reducing a compoundhaving a —C(O)—NH— or —NH—C(O)— linker, respectively, with, for example,sodium borohydride. Alternatively, compounds that have —NHCH₂— linkerscan be prepared by reacting aldehyde (f) with amine (XX) followed byreduction of the shift base with sodium borohydride as shown in SchemeVIa (see U.S. patent application Ser. No. 10/897,681, filed on Jul. 22,2004, the entire teachings of which are incorporated herein byreference).

Example 2 Inhibition of IL-2 Production

Jurkat cells were placed in a 96 well plate (0.5 million cells per wellin 1% FBS medium) then a test compound of this invention was added atdifferent concentrations. After 10 minutes, the cells were activatedwith PHA (final concentration 2.5 μg/mL) and incubated for 20 hours at37° C. under CO₂. The final volume was 200 μL. Following incubation, thecells were centrifuged and the supernatants collected and stored at −70°C. prior to assaying for IL-2 production. A commercial ELISA kit (IL-2Eli-pair, Diaclone Research, Besancon, France) was used to detectproduction of IL-2, from which dose response curves were obtained. TheIC₅₀ value was calculated as the concentration at which 50% of maximumIL-2 production after stimulation was inhibited versus a non-stimulationcontrol.

Compound # IC₅₀ (nM) 6 6 7 4 8 3 10 2 13 14 14 16 15 98 16 15 17 2 18 1219 7 20 12 21 31 67 7 68 38 69 73 70 9 71 17 72 17 73 17 74 25 75 98 769 77 11 78 10 79 10 80 180

Inhibition of other cytokines, such as IL-4, IL-5, IL-13, GM-CSF, TNF-α,and INF-γ, can be tested in a similar manner using a commerciallyavailable ELISA kit for each cytokine.

Example 3 Patch Clamp Studies of Inhibition of I_(CRAC) Current in RBLCells, Jurkat Cells, and Primary T Cells

In general, a whole cell patch clamp method is used to examine theeffects of a compound of the invention on a channel that mediatesI_(crac). In such experiments, a baseline measurement is established fora patched cell. Then a compound to be tested is perfused (or puffed) tocells in the external solution and the effect of the compound onI_(crac) is measured. A compound that modulates I_(CRAC) (e.g.,inhibits) is a compound that is useful in the invention for modulatingCRAC ion channel activity.

1) RBL Cells

Cells

Rat basophilic leukemia cells (RBL-2H3) were grown in DMEM mediasupplemented with 10% fetal bovine serum in an atmosphere of 95% air/5%CO₂. Cells were seeded on glass coverslips 1-3 days before use.

Recording Conditions

Membrane currents of individual cells were recorded using the whole-cellconfiguration of the patch clamp technique with an EPC10 (HEKAElectronik, Lambrecht, Germany). Electrodes (2-5 WΩ in resistance) werefashioned from borosilicate glass capillary tubes (Sutter Instruments,Novato, Calif.). The recordings were done at room temperature.

Intracellular Pipette Solution

The intracellular pipette solution contained Cs-Glutamate 120 mM; CsCl20 mM; CsBAPTA 10 mM; CsHEPES 10 mM; NaCl 8 mM; MgCl₂ 1 mM; IP3 0.02 mM;pH=7.4 adjusted with CsOH. The solution was kept on ice and shieldedfrom light before the experiment was preformed.

Extracellular Solution

The extracellular solution contained NaCl 138 mM; NaHEPES, 10 mM;CsC₁₋₁₀ mM; CaCl₂ 10 mM; Glucose 5.5 mM; KCl 5.4 mM; KH₂PO₄ 0.4 mM;Na₂HPO₄.H₂O 0.3 mM at pH=7.4 adjusted with NaOH.

Compound Treatment

Each compound was diluted from a 10 mM stock in series using DMSO. Thefinal DMSO concentration was always kept at 0.1%.

Experimental Procedure

I_(CRAC) currents were monitored every 2 seconds using a 50 msecprotocol, where the voltage was ramped from −100 mV to +100 mV. Themembrane potential was held at 0 mV between the test ramps. In a typicalexperiment, the peak inward currents would develop within 50-100seconds. Once the I_(CRAC) currents were stabilized, the cells wereperfused with a test compound in the extracellular solution. At the endof an experiment, the remaining I_(CRAC) currents were then challengedwith a control compound (SKF96365, 10 μM) to ensure that the currentcould still be inhibited.

Data Analysis

The I_(CRAC) current level was determined by measuring the inwardcurrent amplitude at −80 mV of the voltage ramp in an off-line analysisusing MATLAB. The I_(CRAC) current inhibition for each concentration wascalculated using peak amplitude in the beginning of the experiment fromthe same cell. The IC₅₀ value and Hill coefficient for each compound wasestimated by fitting all the individual data points to a single Hillequation.

Results

The table below shows the concentration of compounds of the inventionwhich inhibits 50% of the I_(CRAC) current in RBL cells.

Compound Number IC₅₀  8 80 nM 17 40 nM 18 140 nM 20 150 nM SKF96365 4 μM

2) Jurkat Cells

Cells

Jurkat T cells are grown on glass coverslips, transferred to therecording chamber and kept in a standard modified Ringer's solution ofthe following composition: NaCl 145 mM, KCl 2.8 mM, CsCl 10 mM, CaCl₂ 10mM, MgCl₂ 2 mM, glucose 10 mM, HEPES.NaOH 10 mM, pH 7.2.

Extracellular Solution

The external solution contains 10 mM CaNaR, 11.5 mM glucose and a testcompound at various concentrations.

Intracellular Pipette Solution

The standard intracellular pipette solution contains: Cs-glutamate 145mM, NaCl 8 mM, MgCl₂ 1 mM, ATP 0.5 mM, GTP 0.3 mM, pH 7.2 adjusted withCsOH. The solution is supplemented with a mixture of 10 mM Cs-BAPTA and4.3-5.3 mM CaCl₂ to buffer [Ca²⁺]i to resting levels of 100-150 nM.

Patch-Clamp Recordings

Patch-clamp experiments are performed in the tight-seal whole-cellconfiguration at 21-25° C. High-resolution current recordings areacquired by a computer-based patch-clamp amplifier system (EPC-9, HEKA,Lambrecht, Germany). Sylgard®-coated patch pipettes have resistancesbetween 2-4 Mil after filling with the standard intracellular solution.Immediately following establishment of the whole-cell configuration,voltage ramps of 50 ms duration spanning the voltage range of −100 to+100 mV are delivered from a holding potential of 0 mV at a rate of 0.5Hz over a period of 300 to 400 seconds. All voltages are corrected for aliquid junction potential of 10 mV between external and internalsolutions. Currents are filtered at 2.3 kHz and digitized at 100 μsintervals. Capacitive currents and series resistance are determined andcorrected before each voltage ramp using the automatic capacitancecompensation of the EPC-9.

Data Analysis

The very first ramps before activation of I_(CRAC) (usually 1 to 3) aredigitally filtered at 2 kHz, pooled and used for leak-subtraction of allsubsequent current records. The low-resolution temporal development ofinward currents is extracted from the leak-corrected individual rampcurrent records by measuring the current amplitude at −80 mV or avoltage of choice.

3) Primary T Cells

Preparation of Primary T Cells

Primary T cells are obtained from human whole blood samples by adding100 μL of RosetteSep® human T cell enrichment cocktail to 2 mL of wholeblood. The mixture is incubated for 20 minutes at room temperature, thendiluted with an equal volume of PBS containing 2% FBS. The mixture islayered on top of RosetteSep® DM-L density medium and then centrifugedfor 20 minutes at 1200 g at room temperature. The enriched T cells arerecovered from the plasma/density medium interface, then washed with PBScontaining 2% FBS twice, and used in patch clamp experiments followingthe procedure described for RBL cells.

Example 4 Inhibition of Multiple Cytokines in Primary Human PBMCs

Peripheral blood mononuclear cells (PBMCs) are stimulated withphytohemagglutinin (PHA) in the presence of varying concentrations ofcompounds of the invention or cyclosporine A (CsA), a known inhibitor ofcytokine production. Cytokine production is measured using commerciallyavailable human ELISA assay kits (from Cell Science, Inc.) following themanufacturers instructions.

The compounds of the invention are expected to be potent inhibitors ofIL-2, IL-4, IL-5, IL-13, GM-CSF, INF-γ and TNF-α in primary human PBMcells. In addition, compounds of the invention are not expected toinhibit the anti-inflammatory cytokine, IL-10.

Example 5 Inhibition of Degranulation in RBL Cells

Procedure:

The day before the assay is performed, RBL cells, that have been grownto confluence in a 96 well plate, are incubated at 37° C. for at least 2hours. The medium is replaced in each well with 100 μL of fresh mediumcontaining 2 μLg/mL of anti-DNP IgE.

On the following day, the cells are washed once with PRS (2.6 mM glucoseand 0.1% BSA) and 160 μL of PRS is added to each well. A test compoundis added to a well in a 20 μL solution at 10× of the desiredconcentration and incubated for 20 to 40 minutes at 37° C. 20 μL of 10×mouse anti-IgE (10 μL/mL) is added. Maximum degranulation occurs between15 to 40 minutes after addition of anti-IgE.

Compounds of the invention are expected to inhibit degranulation.

Example 6 Inhibition of Chemotaxis in T Cells

T-Cell Isolation:

Twenty ml aliquots of heparinized whole blood (2 pig, 1 human) aresubjected to density gradient centrifugation on Ficoll Hypaque. Thebuffy coat layers representing peripheral blood mononuclear cells(PBMCs) containing lymphocytes and monocytes are washed once,resuspended in 12 ml of incomplete RPMI 1640 and then placed ingelatin-coated T75 culture flasks for 1 hr at 37° C. The non-adherentcells, representing peripheral blood lymphocytes (PBLs) depleted ofmonocytes, are resuspended in complete RPMI media and placed in looselypacked activated nylon wool columns that have been equilibrated withwarm media. After 1 hr at 37° C., the non-adherent T cell populationsare eluted by washing of the columns with additional media. The T cellpreparations are centrifuged, resuspended in 5 ml of incomplete RPMI,and counted using a hemocytometer.

Cell Migration Assay:

Aliquots of each T cell preparation are labeled with Calcien AM(TefLabs) and suspended at a concentration of 2.4×10⁶/ml inHEPES-buffered Hank's Balanced Salt Solution containing 1.83 mM CaCl₂and 0.8 mM MgCl₂, pH 7.4 (HHBSS). An equal volume of HHBSS containing 0,20 nM, 200 nM or 2000 nM of compound 1 or 20 nM EDTA is then added andthe cells incubated for 30 min at 37° C. Fifty μl aliquots of the cellsuspensions (60,000 cells) are placed on the membrane (pore size 5 μm)of a Neuroprobe ChemoTx 96 well chemotaxis unit that have been affixedover wells containing 10 ng/ml MIP-1α in HHBSS. The T cells are allowedto migrate for 2 hr at 37° C., after which the apical surface of themembrane is wiped clean of cells. The chemotaxis units are then placedin a CytoFlour 4000 (PerSeptive BioSystems) and the fluorescence of eachwell measured (excitation and emission wavelengths of 450 and 530 nm,respectively). The number of migrating cells in each well is determinedfrom a standard curve generated from measuring the fluorescence ofserial two-fold dilutions of the labeled cells placed in the lower wellsof the chemotaxis unit prior to affixing the membrane.

Compounds of the invention are expected to inhibit chemotactic responseof T cells.

All publications, patent applications, patents, and other documentscited herein are incorporated by reference in their entirety. In case ofconflict, the present specification, including definitions, willcontrol. In addition, the materials, methods, and examples areillustrative only and not intended to be limiting in any way.

From the foregoing description, it will be apparent that variations andmodifications may be made to the invention described herein. Suchembodiments are also within the scope of the following claims.

We claim:
 1. A method of inhibiting immune cell activation comprisingadministering to the cell a compound represented by structural formula(I):

or a pharmaceutically acceptable salt thereof, wherein: Y₁ is amonocyclic optionally substituted aryl or a monocyclic optionallysubstituted heteroaryl, provided that Y₁ is not a substituted isoxazolylor a substituted 1H-pyrrolyl; L₁ is a linker selected from the groupconsisting of —NHCH₂—, —CH₂NH—, —NR—C(O)—, —OC(O)—, —C(O)O—, —C(S)—,—NR—C(S)—, and —C(S)—NR—; one of X₁ or X₂ is CH or CZ and the other isN; each Z is independently selected from the group consisting of a loweralkyl, a lower haloalkyl, a halo, a lower alkoxy, a lower alkylsulfanyl, —S(O)_(p)-alkyl, —C(O)NRR, —(CH₂)_(k)NRR, —(CH₂)_(k)OR,—(CH₂)_(k)SR, cyano, nitro, and lower haloalkoxy; R, for each occurrenceis independently selected from —H or an alkyl; R₃ is H, an alkyl, ahaloalkyl, a halo, a haloalkoxy, —OR₅, —SR₅, or —NR₆R₇; R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, thiazol-5-yl,[1,3,4]oxadiazol-2-yl, pyridin-3-yl, or pyridin-2-yl; R₅, for eachoccurrence, is independently, H, an optionally substituted alkyl, anoptionally substituted alkenyl, an optionally substituted alkynyl, anoptionally substituted cycloalkyl, an optionally substitutedcycloalkenyl, an optionally substituted heterocyclyl, an optionallysubstituted aryl, an optionally substituted heteroaryl, an optionallysubstituted aralkyl, or an optionally substituted heteraralkyl; R₆ andR₇, for each occurrence are, independently, H, an optionally substitutedalkyl, an optionally substituted alkenyl, an optionally substitutedalkynyl, an optionally substituted cycloalkyl, an optionally substitutedcycloalkenyl, an optionally substituted heterocyclyl, an optionallysubstituted aryl, an optionally substituted heteroaryl, an optionallysubstituted aralkyl, or an optionally substituted heteraralkyl; or R₆and R₇ taken together with the nitrogen to which they are attached arean optionally substituted heterocyclyl or optionally substitutedheteroaryl; q, for each occurrence, is independently, an integer from 1to 3; k is for each occurrence, is independently, an integer from 1 to4; n is zero, 1 or 2; and p, for each occurrence, is independently 1 or2.
 2. The method of claim 1, wherein Y₁ is an optionally substitutedphenyl, an optionally substituted pyridinyl, an optionally substitutedpyridazinyl, an optionally substituted isothiazolyl, an optionallysubstituted thiazolyl, an optionally substituted triazolyl, anoptionally substituted oxadiazolyl, an optionally substituted oxazolyl,an optionally substituted thiadiazolyl, or an optionally substitutedthiophenyl.
 3. The method of claim 2, wherein Y₁ is an optionallysubstituted phenyl or an optionally substituted thiadiazolyl.
 4. Themethod of claim 3, wherein Y₁ is an optionally substituted phenyl. 5.The method of claim 4, wherein Y₁ is substituted with one to twosubstituents.
 6. The method of claim 5, wherein the one to twosubstituents are each independently a lower alkyl or a halo.
 7. Themethod of claim 6, wherein Y₁ is a difluorophenyl.
 8. The method ofclaim 3, wherein Y₁ is 4-methyl-1,2,3-thiadiazol-5-yl.
 9. The method ofclaim 1, wherein L₁ is —NR—C(O)—.
 10. The method of claim 1, wherein Ris —H.
 11. The method of claim 1, wherein R₃ is —H, chloro, fluoro,bromo, methyl, or methoxy.
 12. The method of claim 1, wherein n is 0.13. The method of claim 1, wherein n is 1 and Z is methyl.
 14. Themethod of claim 1, wherein X₁ is N.
 15. The method of claim 14, whereinX₂ is CH.
 16. The method of claim 1, wherein X₂ is N.
 17. The method ofclaim 16, wherein X₁ is CH.
 18. The method of claim 1, wherein: Y₁ is anoptionally substituted phenyl, an optionally substituted pyridinyl, anoptionally substituted pyridazinyl, an optionally substitutedisothiazolyl, an optionally substituted thiazolyl, an optionallysubstituted triazolyl, an optionally substituted oxadiazolyl, anoptionally substituted oxazolyl, an optionally substituted thiadiazolyl,or an optionally substituted thiophenyl; one of X₁ or X₂ is CH; and n is0.
 19. The method of claim 18, wherein L₁ is —NH—C(O)—.
 20. The methodof claim 19, wherein R₃ is —H, chloro, fluoro, bromo, methyl, ormethoxy.
 21. The method of claim 20, wherein Y₁ is a difluorophenyl. 22.The method of claim 20, wherein Y₁ is 4-methyl-1,2,3-thiadiazol-5-yl.23. The method of claim 1, wherein the compound is selected from thegroup consisting of:2,6-Difluoro-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-[5-(2-Chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;4-methyl-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-1,2,3-thiadiazole-5-carboxamide;3-Methyl-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[5-methyl-6-(3-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[4-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;3-Methyl-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]oxadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]thiadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-(5-(2-methoxy-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamide;2,6-difluoro-N-(5-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)benzamide;2,6-difluoro-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)benzamide;N-(5-(2-chloro-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(thiazol-2-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-3-yl)benzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamidehydrochloric acid salt; and4-chloro-2-fluoro-N-(6-(2-methyl-5-(oxazol-2-yl)phenyl)pyridin-3-yl)benzamide;or a pharmaceutically acceptable salt thereof.
 24. The method of claim1, wherein immune cell activation is inhibited in a subject byadministering the compound to the subject.
 25. The method of claim 24,wherein the subject is human.
 26. A method of inhibiting cytokineproduction in a cell, comprising administering to the cell a compoundrepresented by structural formula (I):

or a pharmaceutically acceptable salt thereof, wherein: Y₁ is amonocyclic optionally substituted aryl or a monocyclic optionallysubstituted heteroaryl, provided that Y₁ is not a substituted isoxazolylor a substituted 1H-pyrrolyl; L₁ is a linker selected from the groupconsisting of —NHCH₂—, —CH₂NH—, —NR—C(O)—, —OC(O)—, —C(O)O—, —C(S)—,—NR—C(S)—, and —C(S)—NR—; one of X₁ or X₂ is CH or CZ and the other isN; each Z is independently selected from the group consisting of a loweralkyl, a lower haloalkyl, a halo, a lower alkoxy, a lower alkylsulfanyl, —S(O)_(p)-alkyl, —C(O)NRR, —(CH₂)_(k)NRR, —(CH₂)_(k)OR,—(CH₂)_(k)SR, cyano, nitro, and lower haloalkoxy; R, for each occurrenceis independently selected from —H or an alkyl; R₃ is H, an alkyl, ahaloalkyl, a halo, a haloalkoxy, —OR₅, —SR₅, or —NR₆R₇; R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, thiazol-5-yl,[1,3,4]oxadiazol-2-yl, pyridin-3-yl, or pyridin-2-yl; R₅, for eachoccurrence, is independently, —H, an optionally substituted alkyl, anoptionally substituted alkenyl, an optionally substituted alkynyl, anoptionally substituted cycloalkyl, an optionally substitutedcycloalkenyl, an optionally substituted heterocyclyl, an optionallysubstituted aryl, an optionally substituted heteroaryl, an optionallysubstituted aralkyl, or an optionally substituted heteraralkyl; R₆ andR₇, for each occurrence are, independently, —H, an optionallysubstituted alkyl, an optionally substituted alkenyl, an optionallysubstituted alkynyl, an optionally substituted cycloalkyl, an optionallysubstituted cycloalkenyl, an optionally substituted heterocyclyl, anoptionally substituted aryl, an optionally substituted heteroaryl, anoptionally substituted aralkyl, or an optionally substitutedheteraralkyl; or R₆ and R₇ taken together with the nitrogen to whichthey are attached are an optionally substituted heterocyclyl oroptionally substituted heteroaryl; q, for each occurrence, isindependently, an integer from 1 to 3; k is for each occurrence, isindependently, an integer from 1 to 4; n is zero, 1 or 2; and p, foreach occurrence, is independently 1 or
 2. 27. The method of claim 26,wherein the compound is selected from the group consisting of:2,6-Difluoro-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-[5-(2-Chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;4-methyl-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-1,2,3-thiadiazole-5-carboxamide;3-Methyl-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[5-methyl-6-(3-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[4-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;3-Methyl-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]oxadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]thiadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-(5-(2-methoxy-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamide;2,6-difluoro-N-(5-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)benzamide;2,6-difluoro-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)benzamide;N-(5-(2-chloro-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(thiazol-2-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-3-yl)benzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamidehydrochloric acid salt; and4-chloro-2-fluoro-N-(6-(2-methyl-5-(oxazol-2-yl)phenyl)pyridin-3-yl)benzamide;or a pharmaceutically acceptable salt thereof.
 28. The method of claim26, wherein cytokine production is inhibited in a subject byadministering the compound to the subject.
 29. The method of claim 28,wherein the subject is human.
 30. The method of claim 26, wherein thecytokine is selected from the group consisting of IL-2, IL-4, IL-5,IL-13, GM-CSF, IFN-γ, TNF-α, and combinations thereof.
 31. A method ofmodulating an ion channel in a cell, wherein the ion channel is involvedin immune cell activation, comprising administering to the cell acompound represented by structural formula (I):

or a pharmaceutically acceptable salt thereof, wherein: Y₁ is amonocyclic optionally substituted aryl or a monocyclic optionallysubstituted heteroaryl, provided that Y₁ is not a substituted isoxazolylor a substituted 1H-pyrrolyl; L₁ is a linker selected from the groupconsisting of —NHCH₂—, —CH₂NH—, —NR—C(O)—, —OC(O)—, —C(O)O—, —C(S)—,—NR—C(S)—, and —C(S)—NR—; one of X₁ or X₂ is CH or CZ and the other isN; each Z is independently selected from the group consisting of a loweralkyl, a lower haloalkyl, a halo, a lower alkoxy, a lower alkylsulfanyl, —S(O)_(p)-alkyl, —C(O)NRR, —(CH₂)_(k)NRR, —(CH₂)_(k)OR,—(CH₂)_(k)SR, cyano, nitro, and lower haloalkoxy; R, for each occurrenceis independently selected from —H or an alkyl; R₃ is H, an alkyl, ahaloalkyl, a halo, a haloalkoxy, —OR₅, —SR₅, or —NR₆R₇; R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, thiazol-5-yl,[1,3,4]oxadiazol-2-yl, pyridin-3-yl, or pyridin-2-yl; R₅, for eachoccurrence, is independently, —H, an optionally substituted alkyl, anoptionally substituted alkenyl, an optionally substituted alkynyl, anoptionally substituted cycloalkyl, an optionally substitutedcycloalkenyl, an optionally substituted heterocyclyl, an optionallysubstituted aryl, an optionally substituted heteroaryl, an optionallysubstituted aralkyl, or an optionally substituted heteraralkyl; R₆ andR₇, for each occurrence are, independently, —H, an optionallysubstituted alkyl, an optionally substituted alkenyl, an optionallysubstituted alkynyl, an optionally substituted cycloalkyl, an optionallysubstituted cycloalkenyl, an optionally substituted heterocyclyl, anoptionally substituted aryl, an optionally substituted heteroaryl, anoptionally substituted aralkyl, or an optionally substitutedheteraralkyl; or R₆ and R₇ taken together with the nitrogen to whichthey are attached are an optionally substituted heterocyclyl oroptionally substituted heteroaryl; q, for each occurrence, isindependently, an integer from 1 to 3; k is for each occurrence, isindependently, an integer from 1 to 4; n is zero, 1 or 2; and p, foreach occurrence, is independently 1 or
 2. 32. The method of claim 31,wherein the compound is selected from the group consisting of:2,6-Difluoro-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-[5-(2-Chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;4-methyl-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-1,2,3-thiadiazole-5-carboxamide;3-Methyl-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[5-methyl-6-(3-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[4-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;3-Methyl-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]oxadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]thiadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-(5-(2-methoxy-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamide;2,6-difluoro-N-(5-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)benzamide;2,6-difluoro-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)benzamide;N-(5-(2-chloro-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(thiazol-2-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-3-yl)benzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamidehydrochloric acid salt; and4-chloro-2-fluoro-N-(6-(2-methyl-5-(oxazol-2-yl)phenyl)pyridin-3-yl)benzamide;or a pharmaceutically acceptable salt thereof.
 33. The method of claim31, wherein the ion channel is in a subject and it is modulated byadministering the compound to the subject.
 34. The method of claim 33,wherein the subject is human.
 35. The method of claim 33, wherein theion channel is a Ca²⁺-release-activated Ca²⁺ channel (CRAC).
 36. Amethod of inhibiting T-cell and/or B-cell proliferation in response toan antigen, comprising administering to the cell a compound representedby structural formula (I):

or a pharmaceutically acceptable salt thereof, wherein: Y₁ is amonocyclic optionally substituted aryl or a monocyclic optionallysubstituted heteroaryl, provided that Y₁ is not a substituted isoxazolylor a substituted 1H-pyrrolyl; L₁ is a linker selected from the groupconsisting of —NHCH₂—, —CH₂NH—, —NR—C(O)—, —OC(O)—, —C(O)O—, —C(S)—,—NR—C(S)—, and —C(S)—NR—; one of X₁ or X₂ is CH or CZ and the other isN; each Z is independently selected from the group consisting of a loweralkyl, a lower haloalkyl, a halo, a lower alkoxy, a lower alkylsulfanyl, —S(O)_(p)-alkyl, —C(O)NRR, —(CH₂)_(k)NRR, —(CH₂)_(k)OR,—(CH₂)_(k)SR, cyano, nitro, and lower haloalkoxy; R, for each occurrenceis independently selected from —H or an alkyl; R₃ is H, an alkyl, ahaloalkyl, a halo, a haloalkoxy, —OR₅, —SR₅, or —NR₆R₇; R₄ isoxazol-2-yl, oxazol-5-yl, thiazol-2-yl, thiazol-5-yl,[1,3,4]oxadiazol-2-yl, pyridin-3-yl, or pyridin-2-yl; R₅, for eachoccurrence, is independently, —H, an optionally substituted alkyl, anoptionally substituted alkenyl, an optionally substituted alkynyl, anoptionally substituted cycloalkyl, an optionally substitutedcycloalkenyl, an optionally substituted heterocyclyl, an optionallysubstituted aryl, an optionally substituted heteroaryl, an optionallysubstituted aralkyl, or an optionally substituted heteraralkyl; R₆ andR₇, for each occurrence are, independently, —H, an optionallysubstituted alkyl, an optionally substituted alkenyl, an optionallysubstituted alkynyl, an optionally substituted cycloalkyl, an optionallysubstituted cycloalkenyl, an optionally substituted heterocyclyl, anoptionally substituted aryl, an optionally substituted heteroaryl, anoptionally substituted aralkyl, or an optionally substitutedheteraralkyl; or R₆ and R₇ taken together with the nitrogen to whichthey are attached are an optionally substituted heterocyclyl oroptionally substituted heteroaryl; q, for each occurrence, isindependently, an integer from 1 to 3; k is for each occurrence, isindependently, an integer from 1 to 4; n is zero, 1 or 2; and p, foreach occurrence, is independently 1 or
 2. 37. The method of claim 36,wherein the compound is selected from the group consisting of:2,6-Difluoro-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-[5-(2-Chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;4-Methyl-[1,2,3]thiadiazole-5-carboxylic acid[5-(2-chloro-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-amide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;4-methyl-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-1,2,3-thiadiazole-5-carboxamide;3-Methyl-N-[5-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-oxazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[5-methyl-6-(3-oxazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[4-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-methyl-5-(3-oxazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;3-Methyl-N-[5-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-isonicotinamide;3-Methyl-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-isonicotinamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-benzamidehydrochloride;N-[5-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-2-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-3-methyl-isonicotinamide;N-[6-(2-Chloro-5-thiazol-2-yl-phenyl)-pyridin-3-yl]-2,6-difluoro-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[6-(2-methyl-5-oxazol-5-yl-phenyl)-pyridin-3-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]oxadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;2,6-Difluoro-N-[5-(2-methyl-5-[1,3,4]thiadiazol-2-yl-phenyl)-pyridin-2-yl]-benzamide;N-(5-(2-methoxy-5-(oxazol-5-yl)phenyl)pyridin-2-yl)-4-methyl-1,2,3-thiadiazole-5-carboxamide;2,6-difluoro-N-(5-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)benzamide;2,6-difluoro-N-(5-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-2-yl)benzamide;N-(5-(2-chloro-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-2-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(thiazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(thiazol-2-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(1,3,4-oxadiazol-2-yl)phenyl)pyridin-3-yl)benzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamide;N-(6-(2-chloro-5-(oxazol-2-yl)phenyl)pyridin-3-yl)-2,6-difluorobenzamidehydrochloric acid salt;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamide;2,6-Difluoro-N-(6-(2-methyl-5-(oxazol-5-yl)phenyl)pyridin-3-yl)benzamidehydrochloric acid salt; and4-chloro-2-fluoro-N-(6-(2-methyl-5-(oxazol-2-yl)phenyl)pyridin-3-yl)benzamide;or a pharmaceutically acceptable salt thereof.
 38. The method of claim36, wherein T-cell and/or B-cell proliferation is inhibited in a subjectby administering the compound to the subject.
 39. The method of claim38, wherein the subject is human.